[DevTools] Propagate Esc event to the inspected page

Currently, the Esc event does not reach the inspected page when
the user highlights an element in the Elements pane. With this change,
the Esc event will be marked as not handled to allow event propagation.
As the result, on Esc the highlighting will be turned off and the page
will handle the Esc button.

Fixed: 994645
Change-Id: I8aeee3364ee8806f1dc1808ce74647fd75a8b97d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2152369Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Commit-Queue: Alex Rudenko <alexrudenko@chromium.org>
Cr-Commit-Position: refs/heads/master@{#760032}

third_party/blink/renderer/core/inspector/inspector_overlay_agent.cc

@@ -333,7 +333,6 @@ InspectorOverlayAgent::InspectorOverlayAgent(
       v8_session_(v8_session),
       dom_agent_(dom_agent),
       swallow_next_mouse_up_(false),
-      swallow_next_escape_up_(false),
       backend_node_id_to_inspect_(0),
       enabled_(&agent_state_, false),
       show_ad_highlights_(&agent_state_, false),
@@ -721,16 +720,6 @@ WebInputEventResult InspectorOverlayAgent::HandleInputEvent(
     return WebInputEventResult::kHandledSuppressed;
   }
 
-  if (input_event.GetType() == WebInputEvent::kKeyUp &&
-      swallow_next_escape_up_) {
-    const auto& keyboard_event =
-        static_cast<const WebKeyboardEvent&>(input_event);
-    if (keyboard_event.windows_key_code == VKEY_ESCAPE) {
-      swallow_next_escape_up_ = false;
-      return WebInputEventResult::kHandledSuppressed;
-    }
-  }
-
   LocalFrame* frame = GetFrame();
   if (!frame || !frame->View() || !frame->ContentLayoutObject() ||
       !inspect_tool_)
@@ -758,8 +747,7 @@ WebInputEventResult InspectorOverlayAgent::HandleInputEvent(
         static_cast<const WebKeyboardEvent&>(input_event);
     if (keyboard_event.windows_key_code == VKEY_ESCAPE) {
       GetFrontend()->inspectModeCanceled();
-      swallow_next_escape_up_ = true;
-      return WebInputEventResult::kHandledSuppressed;
+      return WebInputEventResult::kNotHandled;
     }
   }
 

third_party/blink/renderer/core/inspector/inspector_overlay_agent.h

@@ -228,7 +228,6 @@ class CORE_EXPORT InspectorOverlayAgent final
   std::unique_ptr<FrameOverlay> frame_overlay_;
   Member<InspectTool> inspect_tool_;
   bool swallow_next_mouse_up_;
-  bool swallow_next_escape_up_;
   DOMNodeId backend_node_id_to_inspect_;
   InspectorAgentState::Boolean enabled_;
   InspectorAgentState::Boolean show_ad_highlights_;