Roll dart to 84ca27a. (flutter#5700)

* Roll dart to 84ca27a.

Changes since last roll:
```
84ca27a Fix File::OpenUri on Windows.
5403f65 Merge existing metadata into new incrementally compiled components.
3cc0a9a Another fix for a race in a test.
4aacaeb [vm/compiler] Fix handling of exception-throwing instructions in DSE
4ff4620 Adjust status lines for safari (take 2)
c5c18a0 Introduce percent decoding in File::OpenUri.
550f294 Move some analysis to analyzer-analysis-server-linux and make analyzer-analysis-server-linux a try bot.
f5de04f Apply resolution to directive annotations.
6d328b7 Correctly parse dartdoc before abstract class
25969b2 Store resolution for abstract class constructor invocation.
973f73b Handle invalid types from front end.
bab152a Fix default in gardening tools
007dcd4 Upgrade package:http to 0.11.3+17.
2519892 Address a race condition in a test.
ed0ccc7 Add more error message mappings
f0560a8 Add error code ArgumentTypeNotAssignable to improve messaging (issue 33712)
660b8b7 [fuchsia] Update path to timezone service
acd8f34 Update safari status
4ab0827 [gn] Remove dart_test_bootfs
1c673b1 Include bounds in type literals
3a1b09d Fix for bug flutter#33660
810cdf8 Add tests for bug flutter#33660
ac05595 Memory file system returns Uint8List from readAsBytes
d26dba1 More positions in dart2 constant evaluator
eafc52a Add a recovery test
8be1ddb Throw FileSystemException from _FileSystemEntityAdaptor when the file does not exist.
98391f2 [vm] Refactoring: move StreamingScopeBuilder out of kernel_binary_flowgraph
6dfc4ef Remove old dart2analyzer not strong status file entries.
32d208d Revert "Adjust status lines for safari"
5da24bb Adjust status lines for safari
c1f6c9d Fix dart2js-hostassert configuration and enable it on the CQ
1717371 Move InferredData to GlobalTypeInferenceResults
403e7c8 Use DataComputer class to implement equivalence based tests
5dbf6da Remove generics where only ir.Node is used
da9705b Split compileLoadedLibraries
04168fa Move more methods to ClassHierarchy.
a4c47af Fix global-inference bug.
3e33c3d Eliminate analysis warnings in pkg/ code.
72f3abc Fix force-strong flag.
e3323ae [vm/inliner] Inline typed data on 32-bit archs.
f5a3af4 [VM] A const bool.fromEnvironment() with an explicit defaultValue of `null` should default to `null`
1a08800 Run analyzer --use-fasta-parser on the language2 tests; update status file.
aa6dc1e [fasta] Resolve redirecting factories invocations after bodies are built
31cd00b Mark the analysis server integration tests as slow.
65ee951 Force tests to fail pending implementation.
d52555c Update the changelog for analyzer changes.
d6cf9b4 Deprecate and remove the implementation of an older flag.
609a191 Basic implementation of MOVE_FILE for files
149c5a0 Improve formatting of errors in golden files
a600171 Update expectations after parser updates
7570fb8 [fasta] Set parent of annotations in BodyBuilder.finishMetadata.
e8ff3d5 Deprecate and ignore the --strong flag on dartanalyzer.
a5b8ed1 Have dart2analyzer no longer use the --no-preview-dart-2 flag in test.py.
58e7402 Initial attempt to analyze stack traces
a07b2a1 Changed all warnings to errors in the language specification.
5b5e36f Remove use of deprecated methods and constants.
1400cf6 Add named configurations to test matrix.
5d2405f Update the status file for slow tests.
9871ad2 [infra] Move fasta legacy mode SDK tests to their own builder
bb69cc1 Add ClassHierarchy to share code between J/KClosedWorld (second attempt)
148013f Re-add tests for MOVE_FILE refactoring.
9873f04 Update service test to not be different in sync async mode
dbd97fb Prep for analyzer 0.32.3, front_end 0.1.3, kernel 0.3.3
6e8332b Remove older analyzer bots.
eeb5449 More slow test status file updates
c339846 [kernel] Move util.dart from bin to lib.
11123b7 Adjust status lines for firefox
620ab34 [vm] Implement reading of parameter annotations from kernel
7d7e39a [build] Move dart2js run for Observatory from python to GN
3c5fe3c Prevent npe when constructor cannot be resolved
d50fa68 Update strong status in host-checked mode
6218c0f Mark analyzer tests as slow.
f39eaf9 [vm] Refactoring: remove dependency of StreamingScopeBuilder on StreamingFlowGraphBuilder
d5ccb53 Remove more uses of isInstanceOf
7007137 Adjustments to dart2js test matrix.
45eee81 Check another case of StaticWarningCode.TYPE_PARAMETER_REFERENCED_BY_STATIC.
4c789e9 Support the instantiation of abstract constructors
d3b4ba3 Revert "Fix flutter#32227 export dynamic from dart:core in analyzer."
aa93fa1 Update documentation of --host-checked.
afaca9f Use field for class hierarchy map
46bfa72 Have the regular analyzer bots test in dart 2 mode.
90e9fec Add changelog entry for language change on int literals
8c63d57 [vm] Refactoring: move out classes independent of StreamingFlowGraphBuilder
aa00933 Update test matrix for dart2js
5352554 Add tests for instance create of an abstract generic class
33f58d5 Add dump-info end to end test
98a2e90 [vm] Combine internal and external allocation into one allocation limit.
2876159 Resolve arguments and type arguments for unresolved invocations.
c99268f Replace handleUnrecoverableError with handleRecoverableError
0ccdc3e Reland: [dart:io] Adds Socket.startConnect
c9fd951 Add file path to ResolutionApplier error message
fb762be Update dart_style to version 1.1.1 in DEPS
db7085a Rename UnresolvedTargetInvocation.
b803d74 Adjusted errors for FutureOr in class headers
c407e83 Delete duplicate key "configurations" in test_matrix.json
b303f5a Add flag --named-configuration (-n) to test.py options.
22b9847 [analyzer][cfe] Don't crash on converting errors with Severity.context
4fd0404 Adjusted circularity prevention rule for type variable subtyping
1467909 Call _completeOnAsyncReturn instead of .complete directly
b7b24e9 Update dart2js-strong status across several suites
11e0015 Update analysis options files.
ed6c096 Remove old entries from pkg/pkg.status.
30807fe [VM interpreter] Fix InterpretCall stub. The stub was marking the thread as executing VM code too early, since the slow path of AllocateArray (called via PushArrayOfArguments) calls into the runtime. With this fix, DeltaBlueClosures can run in fully interpreted mode.
10c13e0 - deprecate strong-mode: options - move those settings to the language: options settings - ignore strong-mode: false in the analysis options file
3a22666 Clearing a LinkedHashMap should not do big allocations
adb4b4a Remove another call to handleUnrecoverableError
fd26d67 Added getLegacyStats until Chrome fully supports new getStats() API.
```

* Update license hash

DEPS

@@ -31,7 +31,7 @@ vars = {
   # Dart is: https://github.com/dart-lang/sdk/blob/master/DEPS.
   # You can use //tools/dart/create_updated_flutter_deps.py to produce
   # updated revision list of existing dependencies.
-  'dart_revision': '64641d014b77bd410e9aa10558522ae26e4210ee',
+  'dart_revision': '84ca27a09ebd6a65cd23ee52d835d89cbe06c574',
 
   'dart_args_tag': '1.4.1',
   'dart_async_tag': '2.0.7',
@@ -46,15 +46,15 @@ vars = {
   'dart_crypto_tag': '2.0.5',
   'dart_csslib_tag': '0.14.1',
   'dart_dart2js_info_tag': '0.5.6+4',
-  'dart_dart_style_tag': '1.1.0',
+  'dart_dart_style_tag': '1.1.1',
   'dart_dartdoc_tag': 'v0.20.1',
   'dart_fixnum_tag': '0.10.5',
   'dart_glob_tag': '1.1.5',
   'dart_html_tag': '0.13.3',
   'dart_http_multi_server_tag': '2.0.4',
   'dart_http_parser_tag': '3.1.1',
   'dart_http_retry_tag': '0.1.1',
-  'dart_http_tag': '0.11.3+16',
+  'dart_http_tag': '0.11.3+17',
   'dart_http_throttle_tag': '1.0.2',
   'dart_intl_tag': '0.15.2',
   'dart_json_rpc_2_tag': '2.0.6',

travis/licenses_golden/licenses_third_party

@@ -1,4 +1,4 @@
-Signature: ba36501c9aa5697d9114574434597320
+Signature: c34d2115c40cb3fe6d67ff2a2274d002
 
 UNUSED LICENSES: