Move PlatformEventDispatcher implementations to the Oilpan heap.

Source/modules/gamepad/GamepadDispatcher.cpp

Index: Source/modules/gamepad/GamepadDispatcher.cpp
diff --git a/Source/modules/gamepad/GamepadDispatcher.cpp b/Source/modules/gamepad/GamepadDispatcher.cpp
index 8a626789dc6e6a536a468060245a8e9e6a4f311d..9be3ac58f326e6d73f77b284438187ecdaa3ea5e 100644
--- a/Source/modules/gamepad/GamepadDispatcher.cpp
+++ b/Source/modules/gamepad/GamepadDispatcher.cpp
@@ -13,8 +13,8 @@ namespace blink {
 
 GamepadDispatcher& GamepadDispatcher::instance()
 {
-    DEFINE_STATIC_LOCAL(GamepadDispatcher, gamepadDispatcher, ());
-    return gamepadDispatcher;
+    DEFINE_STATIC_LOCAL(Persistent<GamepadDispatcher>, gamepadDispatcher, (new GamepadDispatcher()));
+    return *gamepadDispatcher;
 }
 
 void GamepadDispatcher::sampleGamepads(WebGamepads& gamepads)
@@ -30,6 +30,11 @@ GamepadDispatcher::~GamepadDispatcher()
 {
 }
 
+void GamepadDispatcher::trace(Visitor* visitor)
+{
+    PlatformEventDispatcher::trace(visitor);
+}
+
 void GamepadDispatcher::didConnectGamepad(unsigned index, const WebGamepad& gamepad)
 {
     dispatchDidConnectOrDisconnectGamepad(index, gamepad, true);