Bug 1672726 - Part 2: Support dispatching synthesized touch events through parent process; r=ipc-reviewers,botond,nika

in order to support dispatching synthesized touch events to fission oop iframe.

Depends on D112127

Differential Revision: https://phabricator.services.mozilla.com/D112128

dom/base/nsDOMWindowUtils.cpp

@@ -29,6 +29,7 @@
 #include "mozilla/PendingAnimationTracker.h"
 #include "mozilla/ServoStyleSet.h"
 #include "mozilla/SharedStyleSheetCache.h"
+#include "mozilla/StaticPrefs_test.h"
 #include "mozilla/InputTaskManager.h"
 #include "nsIObjectLoadingContent.h"
 #include "nsIFrame.h"
@@ -902,7 +903,7 @@ nsresult nsDOMWindowUtils::SendTouchEventCommon(
     event.mTouches.AppendElement(t);
   }
 
-  nsEventStatus status;
+  nsEventStatus status = nsEventStatus_eIgnore;
   if (aToWindow) {
     RefPtr<PresShell> presShell;
     nsView* view = nsContentUtils::GetViewToDispatchEvent(
@@ -910,14 +911,21 @@ nsresult nsDOMWindowUtils::SendTouchEventCommon(
     if (!presShell || !view) {
       return NS_ERROR_FAILURE;
     }
-    status = nsEventStatus_eIgnore;
     *aPreventDefault = (status == nsEventStatus_eConsumeNoDefault);
     return presShell->HandleEvent(view->GetFrame(), &event, false, &status);
   }
 
-  nsresult rv = widget->DispatchEvent(&event, status);
-  *aPreventDefault = (status == nsEventStatus_eConsumeNoDefault);
-  return rv;
+  if (StaticPrefs::test_events_async_enabled()) {
+    status = widget->DispatchInputEvent(&event).mContentStatus;
+  } else {
+    nsresult rv = widget->DispatchEvent(&event, status);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
+  if (aPreventDefault) {
+    *aPreventDefault = (status == nsEventStatus_eConsumeNoDefault);
+  }
+  return NS_OK;
 }
 
 static_assert(

dom/ipc/BrowserParent.cpp

@@ -1674,6 +1674,25 @@ mozilla::ipc::IPCResult BrowserParent::RecvDispatchKeyboardEvent(
   return IPC_OK();
 }
 
+mozilla::ipc::IPCResult BrowserParent::RecvDispatchTouchEvent(
+    const mozilla::WidgetTouchEvent& aEvent) {
+  nsCOMPtr<nsIWidget> widget = GetWidget();
+  if (!widget) {
+    return IPC_OK();
+  }
+
+  WidgetTouchEvent localEvent(aEvent);
+  localEvent.mWidget = widget;
+
+  for (uint32_t i = 0; i < localEvent.mTouches.Length(); i++) {
+    localEvent.mTouches[i]->mRefPoint =
+        TransformChildToParent(localEvent.mTouches[i]->mRefPoint);
+  }
+
+  widget->DispatchInputEvent(&localEvent);
+  return IPC_OK();
+}
+
 mozilla::ipc::IPCResult BrowserParent::RecvRequestNativeKeyBindings(
     const uint32_t& aType, const WidgetKeyboardEvent& aEvent,
     nsTArray<CommandInt>* aCommands) {

dom/ipc/BrowserParent.h

@@ -413,6 +413,9 @@ class BrowserParent final : public PBrowserParent,
   mozilla::ipc::IPCResult RecvDispatchKeyboardEvent(
       const mozilla::WidgetKeyboardEvent& aEvent);
 
+  mozilla::ipc::IPCResult RecvDispatchTouchEvent(
+      const mozilla::WidgetTouchEvent& aEvent);
+
   mozilla::ipc::IPCResult RecvScrollRectIntoView(
       const nsRect& aRect, const ScrollAxis& aVertical,
       const ScrollAxis& aHorizontal, const ScrollFlags& aScrollFlags,

dom/ipc/PBrowser.ipdl

@@ -641,6 +641,7 @@ parent:
     [Nested=inside_sync] sync DispatchWheelEvent(WidgetWheelEvent event);
     [Nested=inside_sync] sync DispatchMouseEvent(WidgetMouseEvent event);
     [Nested=inside_sync] sync DispatchKeyboardEvent(WidgetKeyboardEvent event);
+    [Nested=inside_sync] sync DispatchTouchEvent(WidgetTouchEvent event);
 
     async InvokeDragSession(IPCDataTransfer[] transfers, uint32_t action,
                             Shmem? visualData,

ipc/ipdl/sync-messages.ini

@@ -785,11 +785,13 @@ description = legacy sync IPC - please add detailed description
 [PBrowser::RequestNativeKeyBindings]
 description = legacy sync IPC - please add detailed description
 [PBrowser::DispatchWheelEvent]
-description = legacy sync IPC - please add detailed description
+description = Only used by automation tests
 [PBrowser::DispatchMouseEvent]
-description = legacy sync IPC - please add detailed description
+description = Only used by automation tests
 [PBrowser::DispatchKeyboardEvent]
-description = legacy sync IPC - please add detailed description
+description = Only used by automation tests
+[PBrowser::DispatchTouchEvent]
+description = Only used by automation tests
 [PBrowser::EnsureLayersConnected]
 description = legacy sync IPC - please add detailed description
 [PBrowser::SetSystemFont]

widget/PuppetWidget.cpp

@@ -403,6 +403,9 @@ nsIWidget::ContentAndAPZEventStatus PuppetWidget::DispatchInputEvent(
       Unused << mBrowserChild->SendDispatchKeyboardEvent(
           *aEvent->AsKeyboardEvent());
       break;
+    case eTouchEventClass:
+      Unused << mBrowserChild->SendDispatchTouchEvent(*aEvent->AsTouchEvent());
+      break;
     default:
       MOZ_ASSERT_UNREACHABLE("unsupported event type");
   }

widget/nsBaseWidget.cpp

@@ -1161,6 +1161,15 @@ nsIWidget::ContentAndAPZEventStatus nsBaseWidget::DispatchInputEvent(
       status.mContentStatus = nsEventStatus_eConsumeDoDefault;
       return status;
     }
+    if (WidgetTouchEvent* touchEvent = aEvent->AsTouchEvent()) {
+      RefPtr<Runnable> r =
+          new DispatchInputOnControllerThread<MultiTouchInput,
+                                              WidgetTouchEvent>(*touchEvent,
+                                                                mAPZC, this);
+      APZThreadUtils::RunOnControllerThread(std::move(r));
+      status.mContentStatus = nsEventStatus_eConsumeDoDefault;
+      return status;
+    }
     // Allow dispatching keyboard events on Gecko thread.
     MOZ_ASSERT(aEvent->AsKeyboardEvent());
   }