Allow mouse-input to be enabled even if the plugin does not have keyboard focus.

remoting/client/plugin/pepper_input_handler.cc

Index: remoting/client/plugin/pepper_input_handler.cc
diff --git a/remoting/client/plugin/pepper_input_handler.cc b/remoting/client/plugin/pepper_input_handler.cc
index 60a2746b8cd0fd2d1db7bb4b2d8623eba1e88f41..b3e51c95df9ed2d61fe121c88be1422d470517f3 100644
--- a/remoting/client/plugin/pepper_input_handler.cc
+++ b/remoting/client/plugin/pepper_input_handler.cc
@@ -24,6 +24,7 @@ PepperInputHandler::PepperInputHandler(
       input_stub_(input_stub),
       callback_factory_(this),
       has_focus_(false),
+      send_mouse_input_when_unfocused_(false),

[Wez, 2014/05/22 01:14:23]

nit: You could call this (and the related method, etc) move_mouse_when_blurred;
setter could then be set_mmwb(bool) (even if the API we export to JS never
really needs the bool=false capability).

[Jamie, 2014/05/22 01:32:09]

Since it controls more than just mouse movements, I prefer to keep this
terminology. I've changed the interface on PIH as you suggest. I was in two
minds as to whether to do the same for the JS API; I decided against it for
consistency with enableMediaSourceRendering, but LMK if you disagree.

       mouse_lock_state_(MouseLockDisallowed),
       wheel_delta_x_(0),
       wheel_delta_y_(0),
@@ -75,7 +76,7 @@ bool PepperInputHandler::HandleInputEvent(const pp::InputEvent& event) {
 
     case PP_INPUTEVENT_TYPE_MOUSEDOWN:
     case PP_INPUTEVENT_TYPE_MOUSEUP: {
-      if (!has_focus_)
+      if (!has_focus_ && !send_mouse_input_when_unfocused_)

[Wez, 2014/05/22 01:14:23]

Should we be filtering these at all? Is there any way we can even receive a
mouse-down without having focus[1]?

[1] Focus is generally either follows-mouse or click-to-focus, so in either case
by the time we see mouse-down, we must have focus, I think.

[Jamie, 2014/05/22 01:32:09]

I wrote up a summary when I added this code:

https://codereview.chromium.org/136093013/diff/60001/remoting/client/plugin/p...

In short, suppressing these clicks is the right thing to do on Mac, and arguably
makes sense on other platforms as well.

         return false;
 
       pp::MouseInputEvent pp_mouse_event(event);
@@ -114,7 +115,7 @@ bool PepperInputHandler::HandleInputEvent(const pp::InputEvent& event) {
     case PP_INPUTEVENT_TYPE_MOUSEMOVE:
     case PP_INPUTEVENT_TYPE_MOUSEENTER:
     case PP_INPUTEVENT_TYPE_MOUSELEAVE: {
-      if (!has_focus_)
+      if (!has_focus_ && !send_mouse_input_when_unfocused_)
         return false;
 
       pp::MouseInputEvent pp_mouse_event(event);
@@ -134,7 +135,7 @@ bool PepperInputHandler::HandleInputEvent(const pp::InputEvent& event) {
     }
 
     case PP_INPUTEVENT_TYPE_WHEEL: {
-      if (!has_focus_)
+      if (!has_focus_ && !send_mouse_input_when_unfocused_)
         return false;
 
       pp::WheelInputEvent pp_wheel_event(event);
@@ -216,6 +217,10 @@ void PepperInputHandler::SetMouseCursor(scoped_ptr<pp::ImageData> image,
   }
 }
 
+void PepperInputHandler::SendMouseInputWhenUnfocused() {
+  send_mouse_input_when_unfocused_ = true;
+}
+
 void PepperInputHandler::MouseLockLost() {
   DCHECK(mouse_lock_state_ == MouseLockOn ||
          mouse_lock_state_ == MouseLockCancelling);