Split content script injections into multiple tasks

third_party/WebKit/public/web/WebFrameClient.h

Index: third_party/WebKit/public/web/WebFrameClient.h
diff --git a/third_party/WebKit/public/web/WebFrameClient.h b/third_party/WebKit/public/web/WebFrameClient.h
index b4b8a74a8b5c643fa364d43ab082f79f6f730e82..ef45bf732a95110e675492268393c0a1d3153597 100644
--- a/third_party/WebKit/public/web/WebFrameClient.h
+++ b/third_party/WebKit/public/web/WebFrameClient.h
@@ -397,6 +397,10 @@ class BLINK_EXPORT WebFrameClient {
   virtual void runScriptsAtDocumentReady(WebLocalFrame*, bool documentIsEmpty) {
   }
 
+  // The frame's window.onload event is about to fire. This method may delay

[haraken, 2017/03/02 03:54:32]

Shall we drop the part of "The frame's window.onload event is about to fire"?
runScriptsAtDocumentIdle may run enough before window.onload, right?

[Kunihiko Sakamoto, 2017/03/06 09:11:06]

document_idle scripts may run enough before window.ounload, but not through this
function. Injection is triggered by runScriptsAtDocumentIdle, or a delayed task
posted by ScriptInjectionManager::RFOHelper::DidFinishDocumentLoad(). This
function is called only just before onload.

So this is a bit different from runScriptsAtDocument{Start,End}. Should we
emphasize that by renaming this, e.g. runScriptsAtDocumentIdleIfNeeded?

+  // window.onload by incrementing LoadEventDelayCount.
+  virtual void runScriptsAtDocumentIdle(WebLocalFrame*) {}
+
   // The 'load' event was dispatched.
   virtual void didHandleOnloadEvents(WebLocalFrame*) {}