Rename apiimpl.Compiler to CompilerImpl.

tests/compiler/dart2js/js_backend_cps_ir.dart

 // Copyright (c) 2014, 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.
 
 // Test that the CPS IR code generator compiles programs and produces the
 // the expected output.
 
 import 'package:async_helper/async_helper.dart';
 import 'package:expect/expect.dart';
 import 'package:compiler/src/apiimpl.dart' show
-    Compiler;
+    CompilerImpl;
 import 'memory_compiler.dart';
 import 'package:compiler/src/js/js.dart' as js;
 import 'package:compiler/src/elements/elements.dart' show
     ClassElement,
     Element;
 
 const String TEST_MAIN_FILE = 'test.dart';
 
 class TestEntry {
   final String source;
   final String expectation;
   final String elementName;
 
   const TestEntry(this.source, [this.expectation])
     : elementName = null;
 
   const TestEntry.forMethod(this.elementName,
       this.source, this.expectation);
 }
 
 String formatTest(Map test) {
   return test[TEST_MAIN_FILE];
 }
 
-String getCodeForMain(Compiler compiler) {
+String getCodeForMain(CompilerImpl compiler) {
   Element mainFunction = compiler.mainFunction;
   js.Node ast = compiler.enqueuer.codegen.generatedCode[mainFunction];
   return js.prettyPrint(ast, compiler).getText();
 }
 
-String getCodeForMethod(Compiler compiler,
+String getCodeForMethod(CompilerImpl compiler,
                         String name) {
   Element foundElement;
   for (Element element in compiler.enqueuer.codegen.generatedCode.keys) {
     if (element.toString() == name) {
       if (foundElement != null) {
         Expect.fail('Multiple compiled elements are called $name');
       }
       foundElement = element;
     }
   }
@@ skipping 10 matching lines @@
   for (TestEntry test in tests) {
     Map files = {TEST_MAIN_FILE: test.source};
     asyncTest(() async {
       Uri uri = Uri.parse('memory:$TEST_MAIN_FILE');
       try {
         CompilationResult result = await runCompiler(
             entryPoint: uri,
             memorySourceFiles: files,
             options: <String>['--use-cps-ir']);
         Expect.isTrue(result.isSuccess);
-        Compiler compiler = result.compiler;
+        CompilerImpl compiler = result.compiler;
         String expectation = test.expectation;
         if (expectation != null) {
           String expected = test.expectation;
           String found = test.elementName == null
               ? getCodeForMain(compiler)
               : getCodeForMethod(compiler, test.elementName);
           if (expected != found) {
             Expect.fail('Expected:\n$expected\nbut found\n$found');
           }
         }
       } catch (e, st) {
         print(e);
         print(st);
         Expect.fail('The following test failed to compile:\n'
                     '${formatTest(files)}');
       }
     });
   }
 }