WebVR: enable Cardboard button compatibility

chrome/browser/android/vr_shell/vr_shell.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/android/vr_shell/vr_shell.h"
 
 #include "base/metrics/histogram_macros.h"
 #include "chrome/browser/android/vr_shell/ui_elements.h"
 #include "chrome/browser/android/vr_shell/ui_interface.h"
 #include "chrome/browser/android/vr_shell/ui_scene.h"
@@ skipping 357 matching lines @@
             FROM_HERE, base::Bind(&device::GvrDeviceProvider::OnDisplayBlur,
                                   delegate_->GetDeviceProvider()));
       }
       html_interface_->SetMode(UiInterface::Mode::MENU);
       // TODO(mthiesse): The page is no longer visible here. We should unfocus
       // or otherwise let it know it's hidden.
     }
   }
 #endif
   if (html_interface_->GetMode() == UiInterface::Mode::WEB_VR) {
+    // Process screen touch events for Cardboard button compatibility.
+    // Also send tap events for controller "touchpad click" events.
+    if (touch_pending_ || controller_->IsButtonUp(
+            gvr::ControllerButton::GVR_CONTROLLER_BUTTON_CLICK)) {
+      touch_pending_ = false;
+      std::unique_ptr<WebGestureEvent> gesture(new WebGestureEvent());
+      gesture->sourceDevice = blink::WebGestureDeviceTouchpad;
+      gesture->timeStampSeconds =
+          (base::TimeTicks::Now() - base::TimeTicks()).InSecondsF();
+      gesture->type = WebInputEvent::GestureTapDown;
+      gesture->data.tapDown.width = 0;
+      gesture->data.tapDown.height = 0;
+      content_input_manager_->ProcessUpdatedGesture(*gesture.get());
+    }
+
     return;
   }
 
   gvr::Vec3f ergo_neutral_pose;
   if (!controller_->IsConnected()) {
     // No controller detected, set up a gaze cursor that tracks the
     // forward direction.
     ergo_neutral_pose = {0.0f, 0.0f, -1.0f};
     controller_quat_ = GetRotationFromZAxis(forward_vector);
   } else {
@@ skipping 640 matching lines @@
            const JavaParamRef<jobject>& ui_web_contents,
            jlong ui_window_android) {
   return reinterpret_cast<intptr_t>(new VrShell(
       env, obj, content::WebContents::FromJavaWebContents(content_web_contents),
       reinterpret_cast<ui::WindowAndroid*>(content_window_android),
       content::WebContents::FromJavaWebContents(ui_web_contents),
       reinterpret_cast<ui::WindowAndroid*>(ui_window_android)));
 }
 
 }  // namespace vr_shell