DevTools: do not reset device emulation upon second client attaching.

Change-Id: Ie90437511d2eda4a5477abde80c083eeb6448db8
Reviewed-on: https://chromium-review.googlesource.com/1239248Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Commit-Queue: Pavel Feldman <pfeldman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#593399}

content/browser/devtools/devtools_session.cc

@@ -58,7 +58,7 @@ void DevToolsSession::Dispose() {
 void DevToolsSession::AddHandler(
     std::unique_ptr<protocol::DevToolsDomainHandler> handler) {
   handler->Wire(dispatcher_.get());
-  handler->SetRenderer(process_host_id_, host_);
+  handler->InitRenderer(process_host_id_, host_);
   handlers_[handler->name()] = std::move(handler);
 }
 
@@ -67,7 +67,7 @@ void DevToolsSession::SetRenderer(int process_host_id,
   process_host_id_ = process_host_id;
   host_ = frame_host;
   for (auto& pair : handlers_)
-    pair.second->SetRenderer(process_host_id_, host_);
+    pair.second->UpdateRenderer(process_host_id_, host_);
 }
 
 void DevToolsSession::SetBrowserOnly(bool browser_only) {

content/browser/devtools/protocol/devtools_domain_handler.cc

@@ -17,6 +17,16 @@ DevToolsDomainHandler::DevToolsDomainHandler(const std::string& name)
 DevToolsDomainHandler::~DevToolsDomainHandler() {
 }
 
+void DevToolsDomainHandler::InitRenderer(int process_host_id,
+                                         RenderFrameHostImpl* frame_host) {
+  SetRenderer(process_host_id, frame_host);
+}
+
+void DevToolsDomainHandler::UpdateRenderer(int process_host_id,
+                                           RenderFrameHostImpl* frame_host) {
+  SetRenderer(process_host_id, frame_host);
+}
+
 void DevToolsDomainHandler::SetRenderer(int process_host_id,
                                         RenderFrameHostImpl* frame_host) {}
 

content/browser/devtools/protocol/devtools_domain_handler.h

@@ -18,13 +18,19 @@ class DevToolsDomainHandler {
   explicit DevToolsDomainHandler(const std::string& name);
   virtual ~DevToolsDomainHandler();
 
-  virtual void SetRenderer(int process_host_id,
-                           RenderFrameHostImpl* frame_host);
+  virtual void InitRenderer(int process_host_id,
+                            RenderFrameHostImpl* frame_host);
+  virtual void UpdateRenderer(int process_host_id,
+                              RenderFrameHostImpl* frame_host);
   virtual void Wire(UberDispatcher* dispatcher);
   virtual Response Disable();
 
   const std::string& name() const { return name_; }
 
+ protected:
+  virtual void SetRenderer(int process_host_id,
+                           RenderFrameHostImpl* frame_host);
+
  private:
   std::string name_;
 

content/browser/devtools/protocol/emulation_handler.cc

@@ -73,14 +73,18 @@ std::vector<EmulationHandler*> EmulationHandler::ForAgentHost(
       host, Emulation::Metainfo::domainName);
 }
 
-void EmulationHandler::SetRenderer(int process_host_id,
-                                   RenderFrameHostImpl* frame_host) {
-  if (host_ == frame_host)
-    return;
-
+void EmulationHandler::InitRenderer(int process_host_id,
+                                    RenderFrameHostImpl* frame_host) {
   host_ = frame_host;
   if (touch_emulation_enabled_)
     UpdateTouchEventEmulationState();
+}
+
+void EmulationHandler::UpdateRenderer(int process_host_id,
+                                      RenderFrameHostImpl* frame_host) {
+  if (host_ == frame_host)
+    return;
+  InitRenderer(process_host_id, frame_host);
   UpdateDeviceEmulationState();
 }
 

content/browser/devtools/protocol/emulation_handler.h

@@ -32,8 +32,10 @@ class EmulationHandler : public DevToolsDomainHandler,
       DevToolsAgentHostImpl* host);
 
   void Wire(UberDispatcher* dispatcher) override;
-  void SetRenderer(int process_host_id,
-                   RenderFrameHostImpl* frame_host) override;
+  void InitRenderer(int process_host_id,
+                    RenderFrameHostImpl* frame_host) override;
+  void UpdateRenderer(int process_host_id,
+                      RenderFrameHostImpl* frame_host) override;
 
   Response Disable() override;
 

third_party/WebKit/LayoutTests/inspector-protocol/emulation/device-emulation-multiclient-expected.txt

+Tests that device emulation is not reset upon second client attach.
+Emulating device: 1200x1000x1
+1200 x 1000
+Creating a new session
+1200 x 1000
+

third_party/WebKit/LayoutTests/inspector-protocol/emulation/device-emulation-multiclient.js

+(async function(testRunner) {
+  var {page, session, dp} = await testRunner.startBlank('Tests that device emulation is not reset upon second client attach.');
+
+  var DeviceEmulator = await testRunner.loadScript('../resources/device-emulator.js');
+  var deviceEmulator = new DeviceEmulator(testRunner, session);
+
+  await deviceEmulator.emulate(1200, 1000, 1);
+  testRunner.log(await session.evaluate(`document.body.clientWidth + ' x ' + document.body.clientHeight`));
+  testRunner.log('Creating a new session');
+  await page.createSession();
+  testRunner.log(await session.evaluate(`document.body.clientWidth + ' x ' + document.body.clientHeight`));
+  testRunner.completeTest();
+})