Clean up calls to RenderWidget::GetWebWidget().

All calls to GetWebWidget() should either DCHECK that the WebWidget exists, or
else have a conditional with appropriate behavior if the WebWidget does not.

Bug: 995981
Change-Id: I32e148efe04c5a889b0b26ad1d7a6ca9eba8752d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1771052
Auto-Submit: Erik Chen <erikchen@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Commit-Queue: Erik Chen <erikchen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#690779}

content/renderer/input/render_widget_input_handler.cc

@@ -227,6 +227,12 @@ RenderWidgetInputHandler::~RenderWidgetInputHandler() {}
 viz::FrameSinkId RenderWidgetInputHandler::GetFrameSinkIdAtPoint(
     const gfx::PointF& point,
     gfx::PointF* local_point) {
+  // This method must only be called on a local root, which is guaranteed to
+  // have a WebWidget.
+  // TODO(https://crbug.com/995981): Eventually we should be able to remote this
+  // DCHECK, since RenderWidget's lifetime [and thus this instance's] will be
+  // synchronized with the WebWidget.
+  DCHECK(widget_->GetWebWidget());
   gfx::PointF point_in_pixel(point);
   if (widget_->compositor_deps()->IsUseZoomForDSFEnabled()) {
     point_in_pixel = gfx::ConvertPointToPixel(
@@ -264,6 +270,13 @@ viz::FrameSinkId RenderWidgetInputHandler::GetFrameSinkIdAtPoint(
 
 WebInputEventResult RenderWidgetInputHandler::HandleTouchEvent(
     const blink::WebCoalescedInputEvent& coalesced_event) {
+  // This method must only be called on non-frozen RenderWidget, which is
+  // guaranteed to have a WebWidget.
+  // TODO(https://crbug.com/995981): Eventually we should be able to remote this
+  // DCHECK, since RenderWidget's lifetime [and thus this instance's] will be
+  // synchronized with the WebWidget.
+  DCHECK(widget_->GetWebWidget());
+
   const WebInputEvent& input_event = coalesced_event.Event();
 
   if (input_event.GetType() == WebInputEvent::kTouchScrollStarted) {
@@ -296,6 +309,13 @@ void RenderWidgetInputHandler::HandleInputEvent(
     const blink::WebCoalescedInputEvent& coalesced_event,
     const ui::LatencyInfo& latency_info,
     HandledEventCallback callback) {
+  // This method must only be called on non-frozen RenderWidget, which is
+  // guaranteed to have a WebWidget.
+  // TODO(https://crbug.com/995981): Eventually we should be able to remote this
+  // DCHECK, since RenderWidget's lifetime [and thus this instance's] will be
+  // synchronized with the WebWidget.
+  DCHECK(widget_->GetWebWidget());
+
   const WebInputEvent& input_event = coalesced_event.Event();
   base::AutoReset<bool> handling_input_event_resetter(&handling_input_event_,
                                                       true);
@@ -583,6 +603,13 @@ void RenderWidgetInputHandler::HandleInjectedScrollGestures(
     std::vector<InjectScrollGestureParams> injected_scroll_params,
     const WebInputEvent& input_event,
     const ui::LatencyInfo& original_latency_info) {
+  // This method must only be called on non-frozen RenderWidget, which is
+  // guaranteed to have a WebWidget.
+  // TODO(https://crbug.com/995981): Eventually we should be able to remote this
+  // DCHECK, since RenderWidget's lifetime [and thus this instance's] will be
+  // synchronized with the WebWidget.
+  DCHECK(widget_->GetWebWidget());
+
   DCHECK(injected_scroll_params.size());
 
   base::TimeTicks original_timestamp;

content/renderer/render_widget.cc

@@ -722,12 +722,6 @@ void RenderWidget::PrepareForClose() {
 
 void RenderWidget::OnSynchronizeVisualProperties(
     const VisualProperties& original_params) {
-  // TODO:(https://crbug.com/995981): If there is no WebWidget, then the
-  // RenderWidget should also be destroyed, and this conditional should not be
-  // necessary.
-  if (!GetWebWidget())
-    return;
-
   TRACE_EVENT0("renderer", "RenderWidget::OnSynchronizeVisualProperties");
 
   VisualProperties params = original_params;
@@ -1135,6 +1129,11 @@ void RenderWidget::RequestNewLayerTreeFrameSink(
 
 void RenderWidget::DoRequestNewLayerTreeFrameSink(
     LayerTreeFrameSinkCallback callback) {
+  // TODO:(https://crbug.com/995981): If there is no WebWidget, then the
+  // RenderWidget should also be destroyed, and this DCHECK should not be
+  // necessary.
+  DCHECK(GetWebWidget());
+
   // TODO(jonross): have this generated by the LayerTreeFrameSink itself, which
   // would then handle binding.
   mojom::RenderFrameMetadataObserverPtr ptr;
@@ -1572,6 +1571,10 @@ void RenderWidget::ResizeWebWidget() {
                                          browser_controls_shrink_blink_size_);
     return;
   }
+  // TODO:(https://crbug.com/995981): If there is no WebWidget, then the
+  // RenderWidget should also be destroyed, and this DCHECK should not be
+  // necessary.
+  DCHECK(GetWebWidget());
   GetWebWidget()->Resize(size);
 }
 
@@ -2564,6 +2567,15 @@ void RenderWidget::SetHidden(bool hidden) {
 }
 
 void RenderWidget::SetIsFullscreen(bool fullscreen) {
+  // TODO:(https://crbug.com/995981): If there is no WebWidget, then the
+  // RenderWidget should also be destroyed, and this conditional should not be
+  // necessary.
+  // We intentionally avoid setting internal state so that the next time visual
+  // properties are synchronized, state will be correctly propagated to the
+  // WebWidget.
+  if (!GetWebWidget())
+    return;
+
   if (fullscreen == is_fullscreen_granted_)
     return;
   is_fullscreen_granted_ = fullscreen;