Issue 1:
The change in #13567 (originally #12944) dramatically increased the size of the gallery release builds.

cc @szakarias

Issue 2:
I'm not sure what was changed, but I suddenly couldn't run my app on Android devices. I've already tried flutter clean. Please see the console output below. Thanks!

$ flutter run
Launching lib/main.dart on Nexus 5 in debug mode...
Initializing gradle... 0.9s
Resolving dependencies... 0.9s
Running 'gradlew assembleDebug'...
D8: Program type already present: com.example.perfdiagnosisdemo.MainActivity
java.lang.RuntimeException: com.android.builder.dexing.DexArchiveMergerException: Error while merging dex archives: /Users/taodong/Code/flutter_projects/perf_diagnosis_demo/build/app/intermediates/transforms/dexBuilder/debug/13, /Users/taodong/Code/flutter_projects/perf_diagnosis_demo/build/app/intermediates/transforms/dexBuilder/debug/14, /Users/taodong/Code/flutter_projects/perf_diagnosis_demo/build/app/intermediates/transforms/externalLibsDexMerger/debug/0
at java.util.concurrent.ForkJoinTask$AdaptedCallable.exec(ForkJoinTask.java:1431)
at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289)
at java.util.concurrent.ForkJoinTask.externalAwaitDone(ForkJoinTask.java:326)
at java.util.concurrent.ForkJoinTask.doJoin(ForkJoinTask.java:391)
at java.util.concurrent.ForkJoinTask.join(ForkJoinTask.java:719)
at com.google.common.collect.ImmutableList.forEach(ImmutableList.java:397)
at com.android.build.gradle.internal.transforms.DexMergerTransform.transform(DexMergerTransform.java:221)
at com.android.build.gradle.internal.pipeline.TransformTask$2.call(TransformTask.java:221)
at com.android.build.gradle.internal.pipeline.TransformTask$2.call(TransformTask.java:217)
at com.android.builder.profile.ThreadRecorder.record(ThreadRecorder.java:102)
at com.android.build.gradle.internal.pipeline.TransformTask.transform(TransformTask.java:212)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:73)
at org.gradle.api.internal.project.taskfactory.IncrementalTaskAction.doExecute(IncrementalTaskAction.java:46)
at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:39)
at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:26)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter$1.run(ExecuteActionsTaskExecuter.java:121)
at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:336)
at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:328)
at org.gradle.internal.progress.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:199)
at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:110)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeAction(ExecuteActionsTaskExecuter.java:110)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:92)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:70)
at org.gradle.api.internal.tasks.execution.OutputDirectoryCreatingTaskExecuter.execute(OutputDirectoryCreatingTaskExecuter.java:51)
at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:62)
at org.gradle.api.internal.tasks.execution.ResolveTaskOutputCachingStateExecuter.execute(ResolveTaskOutputCachingStateExecuter.java:54)
at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:60)
at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:97)
at org.gradle.api.internal.tasks.execution.CleanupStaleOutputsExecuter.execute(CleanupStaleOutputsExecuter.java:87)
at org.gradle.api.internal.tasks.execution.ResolveTaskArtifactStateTaskExecuter.execute(ResolveTaskArtifactStateTaskExecuter.java:52)
at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:52)
at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:54)
at org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter.execute(ExecuteAtMostOnceTaskExecuter.java:43)
at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:34)
at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker$1.run(DefaultTaskGraphExecuter.java:248)
at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:336)
at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:328)
at org.gradle.internal.progress.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:199)
at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:110)
at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:241)
at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:230)
at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.processTask(DefaultTaskPlanExecutor.java:123)
at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.access$200(DefaultTaskPlanExecutor.java:79)
at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker$1.execute(DefaultTaskPlanExecutor.java:104)
at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker$1.execute(DefaultTaskPlanExecutor.java:98)
at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.execute(DefaultTaskExecutionPlan.java:626)
at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.executeWithTask(DefaultTaskExecutionPlan.java:581)
at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.run(DefaultTaskPlanExecutor.java:98)
at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:63)
at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:46)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:55)
at java.lang.Thread.run(Thread.java:745)
Caused by: com.android.builder.dexing.DexArchiveMergerException: Error while merging dex archives: /Users/taodong/Code/flutter_projects/perf_diagnosis_demo/build/app/intermediates/transforms/dexBuilder/debug/13, /Users/taodong/Code/flutter_projects/perf_diagnosis_demo/build/app/intermediates/transforms/dexBuilder/debug/14, /Users/taodong/Code/flutter_projects/perf_diagnosis_demo/build/app/intermediates/transforms/externalLibsDexMerger/debug/0
at com.android.builder.dexing.D8DexArchiveMerger.getExceptionToRethrow(D8DexArchiveMerger.java:124)
at com.android.builder.dexing.D8DexArchiveMerger.mergeDexArchives(D8DexArchiveMerger.java:109)
at com.android.build.gradle.internal.transforms.DexMergerTransformCallable.call(DexMergerTransformCallable.java:101)
at com.android.build.gradle.internal.transforms.DexMergerTransformCallable.call(DexMergerTransformCallable.java:36)
at java.util.concurrent.ForkJoinTask$AdaptedCallable.exec(ForkJoinTask.java:1424)
... 57 more
Caused by: com.android.tools.r8.CompilationFailedException: Compilation failed to complete
at com.android.tools.r8.utils.ExceptionUtils.withCompilationHandler(ExceptionUtils.java:76)
at com.android.tools.r8.utils.ExceptionUtils.withD8CompilationHandler(ExceptionUtils.java:45)
at com.android.tools.r8.D8.run(D8.java:67)
at com.android.builder.dexing.D8DexArchiveMerger.mergeDexArchives(D8DexArchiveMerger.java:107)
... 60 more
Caused by: com.android.tools.r8.utils.AbortException
at com.android.tools.r8.utils.Reporter.failIfPendingErrors(Reporter.java:77)
at com.android.tools.r8.utils.Reporter.fatalError(Reporter.java:58)
at com.android.tools.r8.utils.ExceptionUtils.withCompilationHandler(ExceptionUtils.java:67)
... 63 more

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:transformDexArchiveWithDexMergerForDebug'.
> com.android.build.api.transform.TransformException: java.lang.RuntimeException: com.android.builder.dexing.DexArchiveMergerException: Error while merging dex archives: /Users/taodong/Code/flutter_projects/perf_diagnosis_demo/build/app/intermediates/transforms/dexBuilder/debug/13, /Users/taodong/Code/flutter_projects/perf_diagnosis_demo/build/app/intermediates/transforms/dexBuilder/debug/14, /Users/taodong/Code/flutter_projects/perf_diagnosis_demo/build/app/intermediates/transforms/externalLibsDexMerger/debug/0

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

* Get more help at https://help.gradle.org

BUILD FAILED in 2s 3.3s
Gradle build failed: 1

== Version Info ==

[✓] Flutter (Channel master, v0.5.9-pre.79, on Mac OS X 10.13.6 17G65, locale en-US)
• Flutter version 0.5.9-pre.79 at /Users/taodong/flutter
• Framework revision 3a4ae280e3 (61 minutes ago), 2018-08-17 15:02:39 -0700
• Engine revision 4ee648914f
• Dart version 2.1.0-dev.0.0.flutter-be6309690f

[✓] Android toolchain - develop for Android devices (Android SDK 27.0.3)
• Android SDK at /Users/taodong/Library/Android/sdk
• Android NDK location not configured (optional; useful for native profiling support)
• Platform android-27, build-tools 27.0.3
• Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
• Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1024-b01)
• All Android licenses accepted.

[✓] iOS toolchain - develop for iOS devices (Xcode 9.4)
• Xcode at /Applications/Xcode.app/Contents/Developer
• Xcode 9.4, Build version 9F1027a
• ios-deploy 1.9.2
• CocoaPods version 1.5.3

[✓] Android Studio (version 3.1)
• Android Studio at /Applications/Android Studio.app/Contents
• Flutter plugin version 27.1.1
• Dart plugin version 173.4700
• Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1024-b01)

[✓] IntelliJ IDEA Community Edition (version 2018.1.6)
• IntelliJ at /Applications/IntelliJ IDEA CE.app
• Flutter plugin version 26.0.2
• Dart plugin version 181.4892.1

[!] VS Code (version 1.25.1)
• VS Code at /Applications/Visual Studio Code.app/Contents
• Flutter extension not installed; install from
https://marketplace.visualstudio.com/items?itemName=Dart-Code.flutter

[✓] Connected devices (1 available)
• Nexus 5 • 07e84ccb010aa11a • android-arm • Android 6.0.1 (API 23)