Avoid referencing undead RenderWidget in FrameInputHandlerImpl.

This CL is a refactor with no intended behavior change.

FrameInputHandlerImpl only needs the RenderWidget to perform coordinate
transforms. This functionality is now exposed on RenderView, and undead
RenderWidget will no longer exist in the future.

Bug: 912193
Change-Id: Ibc3b0528c1539dd286558de52a7141161d46fe29
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1838536
Auto-Submit: Erik Chen <erikchen@chromium.org>
Commit-Queue: Daniel Cheng <dcheng@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Reviewed-by: danakj <danakj@chromium.org>
Cr-Commit-Position: refs/heads/master@{#703062}

content/renderer/input/frame_input_handler_impl.cc

@@ -286,7 +286,7 @@ void FrameInputHandlerImpl::SelectRange(const gfx::Point& base,
 
   if (!render_frame_)
     return;
-  RenderWidget* window_widget = render_frame_->render_view()->GetWidget();
+  RenderWidget* window_widget = render_frame_->GetLocalRootRenderWidget();
   HandlingState handling_state(render_frame_, UpdateState::kIsSelectingRange);
   render_frame_->GetWebFrame()->SelectRange(
       window_widget->ConvertWindowPointToViewport(base),
@@ -383,7 +383,7 @@ void FrameInputHandlerImpl::MoveRangeSelectionExtent(const gfx::Point& extent) {
     return;
   HandlingState handling_state(render_frame_, UpdateState::kIsSelectingRange);
   render_frame_->GetWebFrame()->MoveRangeSelectionExtent(
-      render_frame_->render_view()->GetWidget()->ConvertWindowPointToViewport(
+      render_frame_->GetLocalRootRenderWidget()->ConvertWindowPointToViewport(
           extent));
 }
 
@@ -418,7 +418,7 @@ void FrameInputHandlerImpl::MoveCaret(const gfx::Point& point) {
     return;
 
   render_frame_->GetWebFrame()->MoveCaretSelection(
-      render_frame_->render_view()->GetWidget()->ConvertWindowPointToViewport(
+      render_frame_->GetLocalRootRenderWidget()->ConvertWindowPointToViewport(
           point));
 }