Delay Input.dispatchKeyEvent response until after key event ack.

content/browser/devtools/protocol/devtools_protocol_browsertest.cc

Index: content/browser/devtools/protocol/devtools_protocol_browsertest.cc
diff --git a/content/browser/devtools/protocol/devtools_protocol_browsertest.cc b/content/browser/devtools/protocol/devtools_protocol_browsertest.cc
index c6e228fae207390fa561739e6ec6cebed0e89054..75a1d711cf049afb87ac8b7c9b4f1ee262af8d4b 100644
--- a/content/browser/devtools/protocol/devtools_protocol_browsertest.cc
+++ b/content/browser/devtools/protocol/devtools_protocol_browsertest.cc
@@ -186,13 +186,16 @@ class DevToolsProtocolTest : public ContentBrowserTest,
     agent_host_->DispatchProtocolMessage(this, json_command);
     // Some messages are dispatched synchronously.
     // Only run loop if we are not finished yet.
-    if (in_dispatch_ && wait) {
-      waiting_for_command_result_id_ = last_sent_id_;
-      base::RunLoop().Run();
-    }
+    if (in_dispatch_ && wait)
+      WaitForResponse();
     in_dispatch_ = false;
   }
 
+  void WaitForResponse() {
+    waiting_for_command_result_id_ = last_sent_id_;
+    base::RunLoop().Run();
+  }
+
   bool HasValue(const std::string& path) {
     base::Value* value = 0;
     return result_->Get(path, &value);
@@ -409,14 +412,26 @@ class SyntheticKeyEventTest : public DevToolsProtocolTest {
                     int modifier,
                     int windowsKeyCode,
                     int nativeKeyCode,
-                    const std::string& key) {
+                    const std::string& key,
+                    bool wait) {
     std::unique_ptr<base::DictionaryValue> params(new base::DictionaryValue());
     params->SetString("type", type);
     params->SetInteger("modifiers", modifier);
     params->SetInteger("windowsVirtualKeyCode", windowsKeyCode);
     params->SetInteger("nativeVirtualKeyCode", nativeKeyCode);
     params->SetString("key", key);
-    SendCommand("Input.dispatchKeyEvent", std::move(params));
+    SendCommand("Input.dispatchKeyEvent", std::move(params), wait);
+  }
+};
+
+class SyntheticMouseEventTest : public DevToolsProtocolTest {
+ protected:
+  void SendMouseEvent(const std::string& type, int x, int y, bool wait) {
+    std::unique_ptr<base::DictionaryValue> params(new base::DictionaryValue());
+    params->SetString("type", type);
+    params->SetInteger("x", x);
+    params->SetInteger("y", y);
+    SendCommand("Input.dispatchMouseEvent", std::move(params), wait);
   }
 };
 
@@ -435,8 +450,8 @@ IN_PROC_BROWSER_TEST_F(SyntheticKeyEventTest, KeyEventSynthesizeKey) {
   DOMMessageQueue dom_message_queue;
 
   // Send enter (keycode 13).
-  SendKeyEvent("rawKeyDown", 0, 13, 13, "Enter");
-  SendKeyEvent("keyUp", 0, 13, 13, "Enter");
+  SendKeyEvent("rawKeyDown", 0, 13, 13, "Enter", true);
+  SendKeyEvent("keyUp", 0, 13, 13, "Enter", true);
 
   std::string key;
   ASSERT_TRUE(dom_message_queue.WaitForMessage(&key));
@@ -445,8 +460,8 @@ IN_PROC_BROWSER_TEST_F(SyntheticKeyEventTest, KeyEventSynthesizeKey) {
   EXPECT_EQ("\"Enter\"", key);
 
   // Send escape (keycode 27).
-  SendKeyEvent("rawKeyDown", 0, 27, 27, "Escape");
-  SendKeyEvent("keyUp", 0, 27, 27, "Escape");
+  SendKeyEvent("rawKeyDown", 0, 27, 27, "Escape", true);
+  SendKeyEvent("keyUp", 0, 27, 27, "Escape", true);
 
   ASSERT_TRUE(dom_message_queue.WaitForMessage(&key));
   EXPECT_EQ("\"Escape\"", key);
@@ -454,6 +469,59 @@ IN_PROC_BROWSER_TEST_F(SyntheticKeyEventTest, KeyEventSynthesizeKey) {
   EXPECT_EQ("\"Escape\"", key);
 }
 
+IN_PROC_BROWSER_TEST_F(SyntheticKeyEventTest, KeyboardEventAck) {
+  NavigateToURLBlockUntilNavigationsComplete(shell(), GURL("about:blank"), 1);
+  Attach();
+  ASSERT_TRUE(content::ExecuteScript(
+      shell()->web_contents()->GetRenderViewHost(),
+      "document.body.addEventListener('keydown', () => console.log('x'));"));
+
+  scoped_refptr<InputMsgWatcher> filter = new InputMsgWatcher(
+      RenderWidgetHostImpl::From(
+          shell()->web_contents()->GetRenderViewHost()->GetWidget()),
+      blink::WebInputEvent::MouseMove);
+
+  SendCommand("Runtime.enable", nullptr);
+  SendKeyEvent("rawKeyDown", 0, 13, 13, "Enter", false);
+
+  // We expect that the console log message event arrives *before* the input
+  // event ack, and the subsequent command response for Input.dispatchKeyEvent.
+  WaitForNotification("Runtime.consoleAPICalled");
+  EXPECT_THAT(console_messages_, ElementsAre("x"));
+  EXPECT_FALSE(filter->HasReceivedAck());
+  EXPECT_EQ(1u, result_ids_.size());
+
+  WaitForResponse();
+  EXPECT_EQ(2u, result_ids_.size());
+}
+
+IN_PROC_BROWSER_TEST_F(SyntheticMouseEventTest, MouseEventAck) {
+  NavigateToURLBlockUntilNavigationsComplete(shell(), GURL("about:blank"), 1);
+  Attach();
+  ASSERT_TRUE(content::ExecuteScript(
+      shell()->web_contents()->GetRenderViewHost(),
+      "document.body.addEventListener('mousemove', () => console.log('x'));"));
+
+  scoped_refptr<InputMsgWatcher> filter = new InputMsgWatcher(
+      RenderWidgetHostImpl::From(
+          shell()->web_contents()->GetRenderViewHost()->GetWidget()),
+      blink::WebInputEvent::MouseMove);
+
+  SendCommand("Runtime.enable", nullptr);
+  SendMouseEvent("mouseMoved", 15, 15, false);
+
+  // We expect that the console log message event arrives *before* the input
+  // event ack, and the subsequent command response for
+  // Input.dispatchMouseEvent.
+  WaitForNotification("Runtime.consoleAPICalled");
+  EXPECT_THAT(console_messages_, ElementsAre("x"));
+  EXPECT_FALSE(filter->HasReceivedAck());
+  EXPECT_EQ(1u, result_ids_.size());
+
+  WaitForResponse();
+  EXPECT_EQ(2u, result_ids_.size());
+}
+
 namespace {
 bool DecodePNG(std::string base64_data, SkBitmap* bitmap) {
   std::string png_data;