Include build ID in dart2js

dart/lib/compiler/implementation/compiler.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.
 
 
 /**
  * If true, print a warning for each method that was resolved, but not
  * compiled.
  */
 const bool REPORT_EXCESS_RESOLUTION = false;
 
 /**
  * If true, trace information on pass2 optimizations.
  */
 const bool REPORT_PASS2_OPTIMIZATIONS = false;
 
 /**
+ * A string to identify the revision or build.
+ *
+ * This ID is displayed if the compiler crashes and in verbose mode, and is
+ * an aid in reproducing bug reports.
+ *
+ * The actual string is rewritten during the SDK build process.
+ */
+const String BUILD_ID = 'build number could not be determined';
+
+
+/**
  * Contains backend-specific data that is used throughout the compilation of
  * one work item.
  */
 class ItemCompilationContext {
 }
 
 class WorkItem {
   final ItemCompilationContext compilationContext;
   final Element element;
   TreeElements resolutionTree;
@@ skipping 194 matching lines @@
   void internalErrorOnElement(Element element, String message) {
     internalError(message, element: element);
   }
 
   void unhandledExceptionOnElement(Element element) {
     if (hasCrashed) return;
     hasCrashed = true;
     reportDiagnostic(spanFromElement(element),
                      MessageKind.COMPILER_CRASHED.error().toString(),
                      api.Diagnostic.CRASH);
-    // TODO(ahe): Obtain the build ID.
-    var buildId = 'build number could not be determined';
-    print(MessageKind.PLEASE_REPORT_THE_CRASH.message([buildId]));
+    print(MessageKind.PLEASE_REPORT_THE_CRASH.message([BUILD_ID]));
   }
 
   void cancel([String reason, Node node, Token token,
                HInstruction instruction, Element element]) {
     assembledCode = null; // Compilation failed. Make sure that we
                           // don't return a bogus result.
     SourceSpan span = null;
     if (node !== null) {
       span = spanFromNode(node);
     } else if (token !== null) {
@@ skipping 270 matching lines @@
         || libraryName == 'dart:math'
         || libraryName == 'dart:html') {
       library.addToScope(findHelper(const SourceString('JS')), this);
       if (jsIndexingBehaviorInterface !== null) {
         library.addToScope(jsIndexingBehaviorInterface, this);
       }
     }
   }
 
   void runCompiler(Uri uri) {
+    log('compiling $uri ($BUILD_ID)');
     scanBuiltinLibraries();
     mainApp = scanner.loadLibrary(uri, null, uri);
     libraries.forEach((_, library) {
       maybeEnableJSHelper(library);
     });
     final Element main = mainApp.find(MAIN);
     if (main === null) {
       reportFatalError('Could not find $MAIN', mainApp);
     } else {
       if (!main.isFunction()) reportFatalError('main is not a function', main);
@@ skipping 363 matching lines @@
     final endOffset = end.charOffset + end.slowCharCount;
 
     // [begin] and [end] might be the same for the same empty token. This
     // happens for instance when scanning '$$'.
     assert(endOffset >= beginOffset);
     return f(beginOffset, endOffset);
   }
 
   String toString() => 'SourceSpan($uri, $begin, $end)';
 }