chrome/blink: Add functionality for in-product help for media elements.

third_party/WebKit/Source/modules/media_controls/MediaControlsImpl.cpp

Index: third_party/WebKit/Source/modules/media_controls/MediaControlsImpl.cpp
diff --git a/third_party/WebKit/Source/modules/media_controls/MediaControlsImpl.cpp b/third_party/WebKit/Source/modules/media_controls/MediaControlsImpl.cpp
index 9bf2b7bd75b07965ea592663da13bd45c8245d39..efea1136a290526aa469d60c0472eec64299b73f 100644
--- a/third_party/WebKit/Source/modules/media_controls/MediaControlsImpl.cpp
+++ b/third_party/WebKit/Source/modules/media_controls/MediaControlsImpl.cpp
@@ -581,6 +581,7 @@ void MediaControlsImpl::MaybeShow() {
   // Only make the controls visible if they won't get hidden by OnTimeUpdate.
   if (MediaElement().paused() || !ShouldHideMediaControls())
     MakeOpaque();
+  download_button_->UpdateInProductHelpState();

[mlamouri (slow - plz ping), 2017/07/13 21:14:27]

`MakeOpaque()` is what you care about here. I'm afraid you might end up showing
the IPH without the controls being visible.

[Khushal, 2017/07/17 17:52:20]

So I think I wasn't understanding the 2 states on the controls clearly. The
element enables/disables showing of the controls using MaybeShow/Hide. And then
the controls internally manage making themselves visible using
MakeOpaque/transparent. We don't want to show IPH if the controls have been
hidden using Hide(). But we can make them visible for the purpose of showing it.

I updated the MayBeDispatchInProductHelpTrigger to happen only when the panel
IsWanted. And we need to dismiss this IPH if the controls are hidden so Hide is
the only thing that needs to dismiss it. Restructured the code in the button as
well to make this obvious.

 }
 
 void MediaControlsImpl::Hide() {
@@ -588,6 +589,7 @@ void MediaControlsImpl::Hide() {
   panel_->SetIsDisplayed(false);
   if (overlay_play_button_)
     overlay_play_button_->SetIsWanted(false);
+  download_button_->UpdateInProductHelpState();
 }
 
 bool MediaControlsImpl::IsVisible() const {
@@ -643,6 +645,10 @@ bool MediaControlsImpl::ShouldHideMediaControls(unsigned behavior_flags) const {
   if (text_track_list_->IsWanted() || overflow_list_->IsWanted())
     return false;
 
+  // Don't hide the media controls while the in product help is showing.
+  if (download_button_->IsShowingInProductHelp())
+    return false;
+
   return true;
 }
 
@@ -971,6 +977,7 @@ void MediaControlsImpl::OnPlay() {
   UpdatePlayState();
   timeline_->SetPosition(MediaElement().currentTime());
   UpdateCurrentTimeDisplay();
+  download_button_->MaybeDispatchInProductHelpTrigger();
 }
 
 void MediaControlsImpl::OnPlaying() {
@@ -1216,6 +1223,11 @@ void MediaControlsImpl::HideAllMenus() {
     text_track_list_->SetVisible(false);
 }
 
+void MediaControlsImpl::HideControlsIfNecessary() {
+  if (ShouldHideMediaControls())
+    StartHideMediaControlsTimer();

[mlamouri (slow - plz ping), 2017/07/13 21:14:27]

There is at least one other place with this logic. Can you refactor?

Maybe rename the method `StartHideMediaControlsIfNecessary()`

[Khushal, 2017/07/17 17:52:20]

Done.

+}
+
 DEFINE_TRACE(MediaControlsImpl) {
   visitor->Trace(element_mutation_callback_);
   visitor->Trace(resize_observer_);