Migrated test block 27 to Dart 2.0.

tests/corelib/corelib.status

Index: tests/corelib/corelib.status
diff --git a/tests/corelib/corelib.status b/tests/corelib/corelib.status
index f759dfc909a744ed4f5cfc8d259078e06748ed49..3a7f1bf24ee9c877c9a34d41e88e5719a0389c1b 100644
--- a/tests/corelib/corelib.status
+++ b/tests/corelib/corelib.status
@@ -11,9 +11,6 @@ from_environment_const_type_undefined_test: Skip
 int_from_environment2_test: Skip
 int_from_environment3_test: Skip
 int_from_environment_test: Skip
-string_from_environment2_test: Skip
-string_from_environment3_test: Skip
-string_from_environment_test: Skip
 
 [ $compiler == none || $compiler == precompiler || $compiler == app_jit ]
 symbol_test/01: Fail, Pass # bug 11669
@@ -26,7 +23,6 @@ symbol_reserved_word_test/12: RuntimeError # bug 11669
 
 symbol_test/none: Fail # bug 11669
 symbol_operator_test/03: Fail # bug 11669
-string_case_test/01: Fail # Bug 18061
 
 [ $compiler == none && ($runtime == vm || $runtime == flutter)]
 string_trimlr_test/02: RuntimeError # Issue 29060
@@ -86,7 +82,6 @@ iterable_to_list_test/01: RuntimeError # Issue 26501
 
 big_integer_*: Skip # VM specific test.
 compare_to2_test: RuntimeError, OK    # Requires bigint support.
-string_base_vm_test: RuntimeError, OK # VM specific test.
 nan_infinity_test/01: Fail # Issue 11551
 regexp/pcre_test: Pass, Slow # Issue 21593
 regress_r21715_test: RuntimeError # Requires bigint support.
@@ -109,9 +104,6 @@ list_test/01: Fail # Safari bug: Array(-2) seen as dead code.
 string_trimlr_test/01: Fail
 string_trimlr_test/02: RuntimeError # Uses Unicode 6.2.0 or earlier.
 
-[ $compiler == dart2js && ($runtime == ff || $runtime == jsshell) ]
-string_case_test/01: Fail, OK  # Bug in Firefox.
-
 # Analyzer's implementation of fromEnvironment assumes that undefined
 # environment variables have an unspecified value (rather than being
 # null) because it is expected that the user will supply a value when
@@ -137,9 +129,6 @@ duration2_test: StaticWarning, OK # Test generates error on purpose.
 [ $compiler == dart2analyzer && $builder_tag == strong ]
 *: Skip # Issue 28649
 
-[ $system == windows && $arch == x64 ]
-stopwatch_test: Skip  # Flaky test due to expected performance behaviour.
-
 [ $runtime != d8 && $runtime != vm && $runtime != dart_precompiled ]
 # The regexp tests are not verified to work on non d8/vm platforms yet.
 regexp/*: Skip
@@ -197,12 +186,6 @@ int_from_environment3_test/02: MissingCompileTimeError
 int_from_environment3_test/03: MissingCompileTimeError
 int_from_environment3_test/04: MissingCompileTimeError
 int_from_environment3_test/05: MissingCompileTimeError
-string_case_test/01: RuntimeError
-string_from_environment3_test/01: MissingCompileTimeError
-string_from_environment3_test/02: MissingCompileTimeError
-string_from_environment3_test/03: MissingCompileTimeError
-string_from_environment3_test/04: MissingCompileTimeError
-string_from_environment3_test/05: MissingCompileTimeError
 string_trimlr_test/02: RuntimeError
 symbol_operator_test/03: RuntimeError
 symbol_reserved_word_test/04: MissingCompileTimeError
@@ -243,8 +226,6 @@ from_environment_const_type_undefined_test/08: MissingCompileTimeError
 
 # Possible bugs
 format_exception_test: RuntimeError # Flutter Issue 9111
-string_from_environment_test: Fail # Flutter Issue 9111
-string_from_environment2_test: Fail # Flutter Issue 9111
 int_from_environment_test: Fail # Flutter Issue 9111
 int_from_environment2_test: Fail # Flutter Issue 9111
 from_environment_const_type_test/none: Fail # Flutter Issue 9111