Make full GC reduce memory footprint an explicit event in the idle notification handler.

test/unittests/heap/gc-idle-time-handler-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 <limits>
 
 #include "src/heap/gc-idle-time-handler.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace v8 {
@@ skipping 498 matching lines @@
   for (int i = 0; i < GCIdleTimeHandler::kMaxNoProgressIdleTimesPerIdleRound;
        i++) {
     GCIdleTimeAction action = handler()->Compute(idle_time_ms, heap_state);
     EXPECT_EQ(DO_NOTHING, action.type);
   }
   // We should return DONE after not making progress for some time.
   GCIdleTimeAction action = handler()->Compute(idle_time_ms, heap_state);
   EXPECT_EQ(DONE, action.type);
 }
 
+
+TEST_F(GCIdleTimeHandlerTest, ReduceMemory) {
+  GCIdleTimeHandler::HeapState heap_state = DefaultHeapState();
+  double idle_time = GCIdleTimeHandler::kMinTimeForReduceMemory;
+  for (int i = 0; i < GCIdleTimeHandler::kMaxMarkCompactsInIdleRound; i++) {
+    GCIdleTimeAction action = handler()->Compute(idle_time, heap_state);
+    EXPECT_EQ(DO_FULL_GC_COMPACT, action.type);
+    handler()->NotifyIdleMarkCompact();
+  }
+  GCIdleTimeAction action = handler()->Compute(idle_time, heap_state);
+  EXPECT_EQ(DONE, action.type);
+}
+
 }  // namespace internal
 }  // namespace v8