Bug 1524226 - Add LayersId field to WidgetEvent and InputData. r=masayuki

Differential Revision: https://phabricator.services.mozilla.com/D20169

--HG--
extra : moz-landing-system : lando

widget/BasicEvents.h

@@ -9,6 +9,7 @@
 #include <stdint.h>
 
 #include "mozilla/dom/EventTarget.h"
+#include "mozilla/layers/LayersTypes.h"
 #include "mozilla/EventForwards.h"
 #include "mozilla/TimeStamp.h"
 #include "nsCOMPtr.h"
@@ -478,7 +479,8 @@ class WidgetEvent : public WidgetEventTime {
         mLastRefPoint(0, 0),
         mFocusSequenceNumber(0),
         mSpecifiedEventType(nullptr),
-        mPath(nullptr) {
+        mPath(nullptr),
+        mLayersId(layers::LayersId{0}) {
     MOZ_COUNT_CTOR(WidgetEvent);
     mFlags.Clear();
     mFlags.mIsTrusted = aIsTrusted;
@@ -570,6 +572,11 @@ class WidgetEvent : public WidgetEventTime {
 
   nsTArray<EventTargetChainItem>* mPath;
 
+  // The LayersId of the content process that this event should be
+  // dispatched to. This field is only used in the chrome process
+  // and doesn't get remoted to child processes.
+  layers::LayersId mLayersId;
+
   dom::EventTarget* GetDOMEventTarget() const;
   dom::EventTarget* GetCurrentDOMEventTarget() const;
   dom::EventTarget* GetOriginalDOMEventTarget() const;
@@ -580,6 +587,7 @@ class WidgetEvent : public WidgetEventTime {
     mRefPoint = aEvent.mRefPoint;
     // mLastRefPoint doesn't need to be copied.
     mFocusSequenceNumber = aEvent.mFocusSequenceNumber;
+    // mLayersId intentionally not copied, since it's not used within content
     AssignEventTime(aEvent);
     // mFlags should be copied manually if it's necessary.
     mSpecifiedEventType = aEvent.mSpecifiedEventType;

widget/InputData.cpp

@@ -23,7 +23,11 @@ using namespace dom;
 InputData::~InputData() {}
 
 InputData::InputData(InputType aInputType)
-    : mInputType(aInputType), mTime(0), mFocusSequenceNumber(0), modifiers(0) {}
+    : mInputType(aInputType),
+      mTime(0),
+      mFocusSequenceNumber(0),
+      mLayersId{0},
+      modifiers(0) {}
 
 InputData::InputData(InputType aInputType, uint32_t aTime, TimeStamp aTimeStamp,
                      Modifiers aModifiers)
@@ -31,6 +35,7 @@ InputData::InputData(InputType aInputType, uint32_t aTime, TimeStamp aTimeStamp,
       mTime(aTime),
       mTimeStamp(aTimeStamp),
       mFocusSequenceNumber(0),
+      mLayersId{0},
       modifiers(aModifiers) {}
 
 SingleTouchData::SingleTouchData(int32_t aIdentifier,

widget/InputData.h

@@ -89,6 +89,10 @@ class InputData {
   // content, and focus can be reconfirmed for async keyboard scrolling.
   uint64_t mFocusSequenceNumber;
 
+  // The LayersId of the content process that the corresponding WidgetEvent
+  // should be dispatched to.
+  layers::LayersId mLayersId;
+
   Modifiers modifiers;
 
   INPUTDATA_AS_CHILD_TYPE(MultiTouchInput, MULTITOUCH_INPUT)

widget/nsGUIEventIPC.h

@@ -1092,6 +1092,7 @@ struct ParamTraits<mozilla::InputData> {
     WriteParam(aMsg, aParam.mTimeStamp);
     WriteParam(aMsg, aParam.modifiers);
     WriteParam(aMsg, aParam.mFocusSequenceNumber);
+    WriteParam(aMsg, aParam.mLayersId);
   }
 
   static bool Read(const Message* aMsg, PickleIterator* aIter,
@@ -1100,7 +1101,8 @@ struct ParamTraits<mozilla::InputData> {
            ReadParam(aMsg, aIter, &aResult->mTime) &&
            ReadParam(aMsg, aIter, &aResult->mTimeStamp) &&
            ReadParam(aMsg, aIter, &aResult->modifiers) &&
-           ReadParam(aMsg, aIter, &aResult->mFocusSequenceNumber);
+           ReadParam(aMsg, aIter, &aResult->mFocusSequenceNumber) &&
+           ReadParam(aMsg, aIter, &aResult->mLayersId);
   }
 };