Bug 1302350 - part6 : ensure loading process doens't be interrupted even media element can't be played. r=jwwang

We don't want to stop the loading process even we canceled the play operation.

MozReview-Commit-ID: FyPqBlDKYo0

--HG--
extra : rebase_source : fdbc4390a7763bdbe26e8b809d977234bb5360ea

dom/html/HTMLMediaElement.cpp

@@ -3031,6 +3031,7 @@ void
 HTMLMediaElement::Play(ErrorResult& aRv)
 {
   if (!IsAllowedToPlay()) {
+    MaybeDoLoad();
     return;
   }
 
@@ -3049,9 +3050,7 @@ HTMLMediaElement::PlayInternal()
   StopSuspendingAfterFirstFrame();
   SetPlayedOrSeeked(true);
 
-  if (mNetworkState == nsIDOMHTMLMediaElement::NETWORK_EMPTY) {
-    DoLoad();
-  }
+  MaybeDoLoad();
   if (mSuspendedForPreloadNone) {
     ResumeLoad(PRELOAD_ENOUGH);
   }
@@ -3117,9 +3116,18 @@ HTMLMediaElement::PlayInternal()
   return NS_OK;
 }
 
+void
+HTMLMediaElement::MaybeDoLoad()
+{
+  if (mNetworkState == nsIDOMHTMLMediaElement::NETWORK_EMPTY) {
+    DoLoad();
+  }
+}
+
 NS_IMETHODIMP HTMLMediaElement::Play()
 {
   if (!IsAllowedToPlay()) {
+    MaybeDoLoad();
     return NS_OK;
   }
 

dom/html/HTMLMediaElement.h

@@ -1272,6 +1272,9 @@ protected:
   // A method to check whether the media element is allowed to start playback.
   bool IsAllowedToPlay();
 
+  // If the network state is empty and then we would trigger DoLoad().
+  void MaybeDoLoad();
+
   // True if the tab which media element belongs to has been to foreground at
   // least once or activated by manually clicking the unblocking tab icon.
   bool IsTabActivated() const;