Add an internal flag to the dart2js compiler to enable/diable inlining

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;
@@ skipping 77 matching lines @@
   final Map<String, LibraryElement> libraries;
   int nextFreeClassId = 0;
   World world;
   String assembledCode;
   Types types;
 
   final bool enableMinification;
   final bool enableTypeAssertions;
   final bool enableUserAssertions;
 
+  bool disableInlining = false;
+
   // TODO(5074): Remove this field once we don't accept the
   // deprecated parameter specification.
   static final bool REJECT_NAMED_ARGUMENT_AS_POSITIONAL = false;
 
   final Tracer tracer;
 
   CompilerTask measuredTask;
   Element _currentElement;
   LibraryElement coreLibrary;
   LibraryElement coreImplLibrary;
@@ skipping 835 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)';
 }