Revert of Remove IdleNotification call in the main thread of foreground tab.

Source/bindings/core/v8/V8Initializer.cpp

Index: Source/bindings/core/v8/V8Initializer.cpp
diff --git a/Source/bindings/core/v8/V8Initializer.cpp b/Source/bindings/core/v8/V8Initializer.cpp
index 00bfc941a52ca6137a5a9ea499feab51478dfff2..4d16f8c387bb7bed4fbbc17bc501023d96e58470 100644
--- a/Source/bindings/core/v8/V8Initializer.cpp
+++ b/Source/bindings/core/v8/V8Initializer.cpp
@@ -330,6 +330,23 @@
     return false;
 }
 
+static void idleGCTaskInMainThread(double deadlineSeconds)
+{
+    ASSERT(isMainThread());
+    ASSERT(RuntimeEnabledFeatures::v8IdleTasksEnabled());
+    bool gcFinished = false;
+    v8::Isolate* isolate = v8::Isolate::GetCurrent();
+
+    Platform* platform = Platform::current();
+    if (deadlineSeconds > platform->monotonicallyIncreasingTime())
+        gcFinished = isolate->IdleNotificationDeadline(deadlineSeconds);
+
+    if (gcFinished)
+        platform->currentThread()->scheduler()->postIdleTaskAfterWakeup(FROM_HERE, WTF::bind<double>(idleGCTaskInMainThread));
+    else
+        platform->currentThread()->scheduler()->postIdleTask(FROM_HERE, WTF::bind<double>(idleGCTaskInMainThread));
+}
+
 static void timerTraceProfilerInMainThread(const char* name, int status)
 {
     if (!status) {
@@ -398,6 +415,8 @@
     if (RuntimeEnabledFeatures::v8IdleTasksEnabled()) {
         WebScheduler* scheduler = Platform::current()->currentThread()->scheduler();
         V8PerIsolateData::enableIdleTasks(isolate, adoptPtr(new V8IdleTaskRunner(scheduler)));
+        // FIXME: Remove idleGCTaskInMainThread once V8 starts posting idle task explicity.
+        scheduler->postIdleTask(FROM_HERE, WTF::bind<double>(idleGCTaskInMainThread));
     }
 
     isolate->SetEventLogger(timerTraceProfilerInMainThread);