Use the regular start incremental marking strategy in the idle notification.

src/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 174 matching lines @@
   EXPECT_EQ(DONE, action.type);
 }
 
 
 TEST_F(GCIdleTimeHandlerTest, StopEventually2) {
   GCIdleTimeHandler::HeapState heap_state = DefaultHeapState();
   int idle_time_ms = 10;
   for (int i = 0; i < GCIdleTimeHandler::kMaxMarkCompactsInIdleRound; i++) {
     GCIdleTimeAction action = handler()->Compute(idle_time_ms, heap_state);
     EXPECT_EQ(DO_INCREMENTAL_MARKING, action.type);
+    // In this case we emulate incremental marking steps that finish with a
+    // full gc.
     handler()->NotifyIdleMarkCompact();
   }
+  heap_state.can_start_incremental_marking = false;
   GCIdleTimeAction action = handler()->Compute(idle_time_ms, heap_state);
   EXPECT_EQ(DONE, action.type);
 }
 
 
 TEST_F(GCIdleTimeHandlerTest, ContinueAfterStop1) {
   GCIdleTimeHandler::HeapState heap_state = DefaultHeapState();
   heap_state.incremental_marking_stopped = true;
   heap_state.can_start_incremental_marking = false;
   size_t speed = heap_state.mark_compact_speed_in_bytes_per_ms;
@@ skipping 14 matching lines @@
 }
 
 
 TEST_F(GCIdleTimeHandlerTest, ContinueAfterStop2) {
   GCIdleTimeHandler::HeapState heap_state = DefaultHeapState();
   int idle_time_ms = 10;
   for (int i = 0; i < GCIdleTimeHandler::kMaxMarkCompactsInIdleRound; i++) {
     GCIdleTimeAction action = handler()->Compute(idle_time_ms, heap_state);
     if (action.type == DONE) break;
     EXPECT_EQ(DO_INCREMENTAL_MARKING, action.type);
+    // In this case we try to emulate incremental marking steps the finish with
+    // a full gc.
     handler()->NotifyIdleMarkCompact();
   }
+  heap_state.can_start_incremental_marking = false;
   GCIdleTimeAction action = handler()->Compute(idle_time_ms, heap_state);
   EXPECT_EQ(DONE, action.type);
   // Emulate mutator work.
   for (int i = 0; i < GCIdleTimeHandler::kIdleScavengeThreshold; i++) {
     handler()->NotifyScavenge();
   }
+  heap_state.can_start_incremental_marking = true;
   action = handler()->Compute(idle_time_ms, heap_state);
   EXPECT_EQ(DO_INCREMENTAL_MARKING, action.type);
 }
 
 }  // namespace internal
 }  // namespace v8