Reapply "Change SDK/DartEditor versioning scheme to semantic versions."

dart/sdk/lib/_internal/pub/lib/src/sdk.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 /// Operations relative to the user's installed Dart SDK.
 library pub.sdk;
 
 import 'dart:io';
 
 import 'package:path/path.dart' as path;
 
 import 'io.dart';
 import 'version.dart';
 
-/// Matches an Eclipse-style SDK version number. This is four dotted numbers
-/// (major, minor, patch, build) with an optional suffix attached to the build
-/// number.
-final _versionPattern = new RegExp(r'^(\d+)\.(\d+)\.(\d+)\.(\d+.*)$');
-
 /// Gets the path to the root directory of the SDK.
 String get rootDirectory {
   // Assume the Dart executable is always coming from the SDK.
   return path.dirname(path.dirname(Platform.executable));
 }
 
 /// The SDK's revision number formatted to be a semantic version.
 ///
 /// This can be set so that the version solver tests can artificially select
 /// different SDK versions.
 Version version = _getVersion();
 
-/// Is `true` if the current SDK is an unreleased bleeding edge version.
-bool get isBleedingEdge {
-  // The live build is locked to the magical old number "0.1.2+<stuff>".
-  return version.major == 0 && version.minor == 1 && version.patch == 2;
-}
-
-/// Parse an Eclipse-style version number using the SDK's versioning convention.
-Version parseVersion(String version) {
-  // Given a version file like: 0.1.2.0_r17495
-  // We create a semver like:   0.1.2+0.r17495
-  var match = _versionPattern.firstMatch(version);
-  if (match == null) {
-    throw new FormatException("The Dart SDK's 'version' file was not in a "
-        "format pub could recognize. Found: $version");
-  }
-
-  // Semantic versions cannot use "_".
-  var build = match[4].replaceAll('_', '.');
-
-  return new Version(
-      int.parse(match[1]), int.parse(match[2]), int.parse(match[3]),
-      build: build);
-}
-
 /// Determine the SDK's version number.
 Version _getVersion() {
   // Some of the pub integration tests require an SDK version number, but the
   // tests on the bots are not run from a built SDK so this lets us avoid
   // parsing the missing version file.
   var sdkVersion = Platform.environment["_PUB_TEST_SDK_VERSION"];
   if (sdkVersion != null) return new Version.parse(sdkVersion);
 
   // Read the "version" file.
   var revisionPath = path.join(rootDirectory, "version");
   var version = readTextFile(revisionPath).trim();
-  return parseVersion(version);
+  return new Version.parse(version);
 }