[turbofan] Turn JSBuiltinReducer into an AdvancedReducer.

test/unittests/compiler/js-builtin-reducer-unittest.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/compiler/js-builtin-reducer.h"
 #include "src/compiler/js-graph.h"
 #include "src/compiler/node-properties.h"
 #include "src/compiler/typer.h"
 #include "test/unittests/compiler/graph-unittest.h"
 #include "test/unittests/compiler/node-test-utils.h"
 #include "testing/gmock-support.h"
 
 using testing::BitEq;
 using testing::Capture;
 
 namespace v8 {
 namespace internal {
 namespace compiler {
 
 class JSBuiltinReducerTest : public TypedGraphTest {
  public:
   JSBuiltinReducerTest() : javascript_(zone()) {}
 
  protected:
   Reduction Reduce(Node* node, MachineOperatorBuilder::Flags flags =
                                    MachineOperatorBuilder::Flag::kNoFlags) {
     MachineOperatorBuilder machine(zone(), kMachPtr, flags);
     JSGraph jsgraph(isolate(), graph(), common(), javascript(), &machine);
-    JSBuiltinReducer reducer(&jsgraph);
+    // TODO(titzer): mock the GraphReducer here for better unit testing.

[titzer, 2015/06/05 12:30:50]

u wot m8?

+    GraphReducer graph_reducer(zone(), graph());
+    JSBuiltinReducer reducer(&graph_reducer, &jsgraph);
     return reducer.Reduce(node);
   }
 
   Node* MathFunction(const char* name) {
     Handle<Object> m =
         JSObject::GetProperty(isolate()->global_object(),
                               isolate()->factory()->NewStringFromAsciiChecked(
                                   "Math")).ToHandleChecked();
     Handle<JSFunction> f = Handle<JSFunction>::cast(
         JSObject::GetProperty(
@@ skipping 153 matching lines @@
 
       ASSERT_TRUE(r.Changed());
       EXPECT_THAT(r.replacement(), IsTruncateFloat64ToFloat32(p0));
     }
   }
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8