[Refactor] Set is_direct_manipulation in InputHandlerProxy

We kept |touch_scrolling_| simply to be able to set the
|is_direct_manipulation_| bit on the scroll state in ScrollBy. It's
cleaner to simply have InputHandlerProxy set this bit correctly in all
cases.

The majority of this CL is simply adding an extra parameter to the state
creation method in unit tests so that we can set the bit correctly there
too. This was a mechanical change.

Bug: 1016229
Change-Id: If0c46d283fb030f205ffd39cdb0c04dd9e1bd7a5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1981335
Commit-Queue: David Bokan <bokan@chromium.org>
Reviewed-by: Philip Rogers <pdr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#728517}

cc/trees/layer_tree_host_impl.cc

@@ -3850,12 +3850,8 @@ InputHandler::ScrollStatus LayerTreeHostImpl::ScrollBeginImpl(
 
   browser_controls_offset_manager_->ScrollBegin();
 
-  // TODO(majidvp): get rid of touch_scrolling_ and set is_direct_manipulation
-  // in input_handler_proxy instead.
-  touch_scrolling_ = type == InputHandler::TOUCHSCREEN;
   wheel_scrolling_ = type == InputHandler::WHEEL;
   middle_click_autoscrolling_ = type == InputHandler::AUTOSCROLL;
-  scroll_state->set_is_direct_manipulation(touch_scrolling_);
 
   LatchToScroller(scroll_state, scrolling_node);
 
@@ -4642,8 +4638,6 @@ InputHandlerScrollResult LayerTreeHostImpl::ScrollBy(
   float initial_top_controls_offset =
       browser_controls_offset_manager_->ControlsTopOffset();
 
-  scroll_state->set_is_direct_manipulation(touch_scrolling_);
-
   ScrollLatchedScroller(scroll_state);
 
   bool did_scroll_x = scroll_state->caused_scroll_x();

cc/trees/layer_tree_host_impl.h

@@ -1062,7 +1062,6 @@ class CC_EXPORT LayerTreeHostImpl : public InputHandler,
   std::unique_ptr<LayerTreeImpl> recycle_tree_;
 
   InputHandlerClient* input_handler_client_ = nullptr;
-  bool touch_scrolling_ = false;
   bool wheel_scrolling_ = false;
   bool middle_click_autoscrolling_ = false;
   bool scroll_affects_scroll_handler_ = false;

ui/events/blink/input_handler_proxy.cc

@@ -83,6 +83,8 @@ cc::ScrollState CreateScrollStateForGesture(const WebGestureEvent& event) {
       NOTREACHED();
       break;
   }
+  scroll_state_data.is_direct_manipulation =
+      event.SourceDevice() == blink::WebGestureDevice::kTouchscreen;
   return cc::ScrollState(scroll_state_data);
 }