Add messages for more exception types.
Return Future.error instead of throwing exception in git branch.
Reduce viewport size for disclose triangles in file view
Merge branch 'master' into more_exceptions

Conflicts:
	ide/app/lib/exception.dart
Merge pull request #2550 from dart-lang/more_exceptions

[Staged] More exceptions
Added 'Segoe UI' to top of font stack to mitigate Roboto rendered badly on Windows
Adjust margin between disclosure triangles and file/project names
Merge pull request #2632 from ussuri/fix-roboto-on-windows

Added 'Segoe UI' to top of font stack to mitigate Roboto rendered badly on Windows
Small margin adjustment
Fixed NPE in Outline
Merge pull request #2638 from ussuri/resizable-outline-and-better-button

Fixed NPE in Outline
Merge pull request #2626 from ussuri/svg-icons-3

Reduce viewport/target size for disclose triangles in file view
Fix Ace element being truncated after fresh install & project creation
Merge pull request #2641 from ussuri/fix-truncated-ace

Fix Ace element being truncated after fresh install & project creation
Merge remote-tracking branch 'upstream/master' into small-fixes-2
Prevent large dumps of debug info to console on build in non-dev mode