Limit rate of full garbage collections triggered by idle notification.

src/heap/mark-compact.cc

Index: src/heap/mark-compact.cc
diff --git a/src/heap/mark-compact.cc b/src/heap/mark-compact.cc
index de381aab356657374f1e62f083173045d949ded0..f7afc641c4c4af4212175f46f1010d0700abe5a4 100644
--- a/src/heap/mark-compact.cc
+++ b/src/heap/mark-compact.cc
@@ -53,7 +53,8 @@ MarkCompactCollector::MarkCompactCollector(Heap* heap)
       marking_deque_memory_(NULL),
       marking_deque_memory_committed_(false),
       code_flusher_(NULL),
-      have_code_to_deoptimize_(false) {
+      have_code_to_deoptimize_(false),
+      last_mark_compact_time_(0) {
 }
 
 #ifdef VERIFY_HEAP
@@ -878,6 +879,9 @@ void MarkCompactCollector::Finish() {
   }
 
   heap_->incremental_marking()->ClearIdleMarkingDelayCounter();
+  last_mark_compact_time_ = static_cast<size_t>(
+      V8::GetCurrentPlatform()->MonotonicallyIncreasingTime() *
+      static_cast<double>(base::Time::kMillisecondsPerSecond));
 }