Update Dart (1.19.0-dev.0.0) and analyzer (0.27.4-alpha.19).

bin/cache/dart-sdk.version

-1.18.0-dev.4.4
+1.19.0-dev.0.0

examples/flutter_gallery/pubspec.yaml

@@ -2,7 +2,7 @@ name: flutter_gallery
 dependencies:
   intl: '>=0.12.4+2 <0.13.0'
   collection: '>=1.4.0 <2.0.0'
-  string_scanner: '^0.1.5'
+  string_scanner: ^1.0.0
 
   flutter:
     path: ../../packages/flutter

packages/flutter_driver/pubspec.yaml

@@ -20,6 +20,6 @@ dependencies:
     path: '../flutter_test'
 
 dev_dependencies:
-  test: 0.12.13+5
+  test: 0.12.15+1
   mockito: '^0.11.0'
   quiver: '^0.21.4'

packages/flutter_markdown/pubspec.yaml

@@ -8,7 +8,7 @@ dependencies:
   flutter:
     path: ../flutter
   markdown: '^0.9.0'
-  string_scanner: '^0.1.5'
+  string_scanner: ^1.0.0
 
 dev_dependencies:
   flutter_test:

packages/flutter_test/pubspec.yaml

@@ -5,12 +5,12 @@ dependencies:
   # The flutter tools depend on very specific internal implementation
   # details of the 'test' package, which change between versions, so
   # here we pin it precisely to avoid version skew across our packages.
-  test: 0.12.13+5
+  test: 0.12.15+1
 
   # We don't actually depend on 'analyzer', but 'test' and 'flutter_tools' do.
   # We pin the version of analyzer we depend on to avoid version skew across our
   # packages.
-  analyzer: 0.27.4-alpha.16
+  analyzer: 0.27.4-alpha.19
 
   flutter:
     path: ../flutter

packages/flutter_tools/pubspec.yaml

@@ -36,10 +36,10 @@ dependencies:
   # We depend on very specific internal implementation details of the
   # 'test' package, which change between versions, so here we pin it
   # precisely.
-  test: 0.12.13+5
+  test: 0.12.15+1
 
   # Pinned in flutter_test as well.
-  analyzer: 0.27.4-alpha.16
+  analyzer: 0.27.4-alpha.19
 
 dev_dependencies:
   mockito: ^0.11.0