Issue 1:
* Error running Gradle:
Exit code 1 from: /home/travis/build/flutter/flutter sdk/examples/flutter_gallery/android/gradlew app:properties:
Starting a Gradle Daemon (subsequent builds will be faster)
Download https://dl.google.com/dl/android/maven2/com/android/tools/build/gradle/3.1.2/gradle-3.1.2.pom
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Download https://dl.google.com/dl/android/maven2/com/android/tools/analytics-library/tracker/26.1.2/tracker-26.1.2.jar
Download https://dl.google.com/dl/android/maven2/com/android/tools/analytics-library/shared/26.1.2/shared-26.1.2.jar
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Download https://dl.google.com/dl/android/maven2/com/android/tools/dvlib/26.1.2/dvlib-26.1.2.jar
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Download https://dl.google.com/dl/android/maven2/com/android/tools/analytics-library/protos/26.1.2/protos-26.1.2.jar
Download https://jcenter.bintray.com/com/google/errorprone/error_prone_annotations/2.1.2/error_prone_annotations-2.1.2.jar
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Download https://dl.google.com/dl/android/maven2/com/android/tools/build/apksig/3.1.2/apksig-3.1.2.jar
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Download https://jcenter.bintray.com/com/googlecode/json-simple/json-simple/1.1/json-simple-1.1.jar
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Download https://jcenter.bintray.com/com/googlecode/juniversalchardet/juniversalchardet/1.0.3/juniversalchardet-1.0.3.jar
Download https://jcenter.bintray.com/com/squareup/javapoet/1.8.0/javapoet-1.8.0.jar
Download https://jcenter.bintray.com/com/google/code/gson/gson/2.7/gson-2.7.jar
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Download https://jcenter.bintray.com/net/sf/proguard/proguard-base/5.3.3/proguard-base-5.3.3.jar
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Download https://jcenter.bintray.com/org/codehaus/mojo/animal-sniffer-annotations/1.14/animal-sniffer-annotations-1.14.jar
Download https://jcenter.bintray.com/com/google/code/findbugs/jsr305/1.3.9/jsr305-1.3.9.jar
Download https://jcenter.bintray.com/org/apache/httpcomponents/httpclient/4.2.6/httpclient-4.2.6.jar
Download https://jcenter.bintray.com/org/apache/commons/commons-compress/1.12/commons-compress-1.12.jar
Download https://jcenter.bintray.com/org/apache/httpcomponents/httpmime/4.1/httpmime-4.1.jar
Download https://jcenter.bintray.com/net/sf/kxml/kxml2/2.3.0/kxml2-2.3.0.jar
Download https://jcenter.bintray.com/org/jetbrains/annotations/13.0/annotations-13.0.jar
Download https://jcenter.bintray.com/com/sun/activation/javax.activation/1.2.0/javax.activation-1.2.0.jar
Download https://jcenter.bintray.com/org/glassfish/jaxb/jaxb-runtime/2.2.11/jaxb-runtime-2.2.11.jar
Download https://jcenter.bintray.com/commons-logging/commons-logging/1.1.1/commons-logging-1.1.1.jar
Download https://jcenter.bintray.com/org/apache/httpcomponents/httpcore/4.2.5/httpcore-4.2.5.jar
Download https://jcenter.bintray.com/commons-codec/commons-codec/1.6/commons-codec-1.6.jar
Download https://jcenter.bintray.com/org/jvnet/staxex/stax-ex/1.7.7/stax-ex-1.7.7.jar
Download https://jcenter.bintray.com/org/glassfish/jaxb/jaxb-core/2.2.11/jaxb-core-2.2.11.jar
Download https://jcenter.bintray.com/com/sun/xml/fastinfoset/FastInfoset/1.2.13/FastInfoset-1.2.13.jar
Download https://jcenter.bintray.com/javax/xml/bind/jaxb-api/2.2.12-b140109.1041/jaxb-api-2.2.12-b140109.1041.jar
Download https://jcenter.bintray.com/org/glassfish/jaxb/txw2/2.2.11/txw2-2.2.11.jar
Download https://jcenter.bintray.com/com/sun/istack/istack-commons-runtime/2.21/istack-commons-runtime-2.21.jar
Download https://dl.google.com/dl/android/maven2/com/android/tools/build/bundletool/0.1.0-alpha01/bundletool-0.1.0-alpha01.jar
Picked up _JAVA_OPTIONS: -Xmx2048m -Xms512m
Project evaluation failed including an error in afterEvaluate {}. Run with --stacktrace for details of the afterEvaluate {} error.
FAILURE: Build failed with an exception.
* Where:
Build file '/home/travis/build/flutter/flutter sdk/examples/flutter_gallery/android/app/build.gradle' line: 25
* What went wrong:
A problem occurred evaluating project ':app'.
> Could not resolve all files for configuration 'classpath'.
> Could not resolve com.android.tools.build:gradle:3.1.2.
Required by:
unspecified:unspecified:unspecified
> Could not resolve com.android.tools.build:gradle:3.1.2.
> Could not get resource 'https://jcenter.bintray.com/com/android/tools/build/gradle/3.1.2/gradle-3.1.2.pom'.
> Could not HEAD 'https://jcenter.bintray.com/com/android/tools/build/gradle/3.1.2/gradle-3.1.2.pom'.
> Read timed out
* 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 1m 3s
Please review your Gradle project setup in the android/ folder.

build_and_deploy_gallery shard on Travis.

Issue 2:
We should consider detecting network errors in gradle and retrying...

Initializing gradle... 6.3s
Resolving dependencies...
* Error running Gradle:
Exit code 1 from: /home/travis/build/flutter/flutter sdk/examples/flutter_gallery/android/gradlew app:properties:
Starting a Gradle Daemon (subsequent builds will be faster)
Picked up _JAVA_OPTIONS: -Xmx2048m -Xms512m
FAILURE: Build failed with an exception.
* What went wrong:
A problem occurred configuring root project 'android'.
> Could not resolve all files for configuration ':classpath'.
> Could not resolve com.android.tools.build:gradle:3.1.2.
Required by:
project :
> Could not resolve com.android.tools.build:gradle:3.1.2.
> Could not get resource 'https://dl.google.com/dl/android/maven2/com/android/tools/build/gradle/3.1.2/gradle-3.1.2.pom'.
> Could not GET 'https://dl.google.com/dl/android/maven2/com/android/tools/build/gradle/3.1.2/gradle-3.1.2.pom'.
> Remote host closed connection during handshake
* 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 24s
Please review your Gradle project setup in the android/ folder.