Merge the dart:uri library into dart:core and update the Uri class

tests/standalone/standalone.status

Index: tests/standalone/standalone.status
diff --git a/tests/standalone/standalone.status b/tests/standalone/standalone.status
index 6317daafa6e9dd2e7f9a1dff53e545e3edae1641..5d7b8a735e78547e1677f5cf5051045b32961f6b 100644
--- a/tests/standalone/standalone.status
+++ b/tests/standalone/standalone.status
@@ -60,6 +60,8 @@ debugger/*: Skip # Do not run standalone debugger tests in browser.
 # package test issue 7392
 package/package1_test: Fail
 package/package_test: Fail
+io/test_runner_test: Fail # Library dart:uri removed.
+io/skipping_dart2js_compilations_test: Skip # Library dart:uri removed.
 
 
 # The dart:io library is created at build time from separate files, and
@@ -104,6 +106,8 @@ package/package_isolate_test: Skip # spawnUri does not work in dart2js. See issu
 debugger/*: Skip # Do not run standalone vm debugger tests with dart2js.
 left_shift_bit_and_op_test: Skip # Integers exceed dart2js precision.
 pow_test: Skip # Precision > 53 bits.
+io/test_runner_test: Fail # Library dart:uri removed.
+io/skipping_dart2js_compilations_test: Skip # Library dart:uri removed.
 
 [ $compiler == dart2js && $jscl ]
 assert_test: Fail, OK # Assumes unspecified fields on the AssertionError.