Fix flaky crashes

Source/core/frame/PlatformEventDispatcher.cpp

Index: Source/core/frame/PlatformEventDispatcher.cpp
diff --git a/Source/core/frame/PlatformEventDispatcher.cpp b/Source/core/frame/PlatformEventDispatcher.cpp
index ef830041074bd43b1bae495015b1d10981c5ea2a..12c0d214f6d4df87a366cdb900fac69c186f5514 100644
--- a/Source/core/frame/PlatformEventDispatcher.cpp
+++ b/Source/core/frame/PlatformEventDispatcher.cpp
@@ -19,9 +19,12 @@ PlatformEventDispatcher::PlatformEventDispatcher()
 void PlatformEventDispatcher::addController(PlatformEventController* controller)
 {
     ASSERT(controller);
-    ASSERT(!m_controllers.contains(controller));
 
-    m_controllers.add(controller);
+    // FIXME: If we can avoid registering a controller twice, we can change

[haraken, 2015/09/04 05:32:45]

FIXME => TODO

[peria, 2015/09/04 05:41:18]

Done.

+    // this 'if' to ASSERT.
+    if (!m_controllers.contains(controller))

[haraken, 2015/09/04 05:32:45]

Would't it be better to early-return if the controller exists in the map?

[peria, 2015/09/04 05:41:18]

Done.

+        m_controllers.add(controller);
+
     if (!m_isListening) {
         startListening();
         m_isListening = true;