Remove ThreadDebugger::endUserGesture() which is unused.

Bug: 826293
Change-Id: I276454b8fbb5b168c84498881e5f2c6223f56426
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2375926Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Mustaq Ahmed <mustaq@chromium.org>
Cr-Commit-Position: refs/heads/master@{#801542}

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

@@ -152,7 +152,7 @@ void ThreadDebugger::PromiseRejectionRevoked(v8::Local<v8::Context> context,
                                      ToV8InspectorStringView(message));
 }
 
-// TODO(mustaq): Fix the caller in v8/src.
+// TODO(mustaq): Is it tied to a specific user action? https://crbug.com/826293
 void ThreadDebugger::beginUserGesture() {
   auto* window = CurrentDOMWindow(isolate_);
   LocalFrame::NotifyUserActivation(
@@ -160,9 +160,6 @@ void ThreadDebugger::beginUserGesture() {
       mojom::blink::UserActivationNotificationType::kDevTools);
 }
 
-// TODO(mustaq): Fix the caller in v8/src.
-void ThreadDebugger::endUserGesture() {}
-
 std::unique_ptr<v8_inspector::StringBuffer> ThreadDebugger::valueSubtype(
     v8::Local<v8::Value> value) {
   static const char kNode[] = "node";

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

@@ -83,7 +83,6 @@ class CORE_EXPORT ThreadDebugger : public v8_inspector::V8InspectorClient,
  private:
   // V8InspectorClient implementation.
   void beginUserGesture() override;
-  void endUserGesture() override;
   std::unique_ptr<v8_inspector::StringBuffer> valueSubtype(
       v8::Local<v8::Value>) override;
   bool formatAccessorsAsProperties(v8::Local<v8::Value>) override;