Expose Gamepad API instance for Cardboard button

chrome/browser/android/vr_shell/vr_shell.cc

Index: chrome/browser/android/vr_shell/vr_shell.cc
diff --git a/chrome/browser/android/vr_shell/vr_shell.cc b/chrome/browser/android/vr_shell/vr_shell.cc
index c32e477f7b76dcd5eecf5d42f5a2828e2f32c90f..139e725b0fb540c8a77de95ceda15091181916cf 100644
--- a/chrome/browser/android/vr_shell/vr_shell.cc
+++ b/chrome/browser/android/vr_shell/vr_shell.cc
@@ -246,10 +246,12 @@ void VrShell::NavigateBack() {
   Java_VrShellImpl_navigateBack(env, j_vr_shell_.obj());
 }
 
-void VrShell::OnTriggerEvent(JNIEnv* env, const JavaParamRef<jobject>& obj) {
+void VrShell::OnTriggerEvent(JNIEnv* env,
+                             const JavaParamRef<jobject>& obj,
+                             bool touched) {
   gl_thread_->task_runner()->PostTask(
-      FROM_HERE,
-      base::Bind(&VrShellGl::OnTriggerEvent, gl_thread_->GetVrShellGl()));
+      FROM_HERE, base::Bind(&VrShellGl::OnTriggerEvent,
+                            gl_thread_->GetVrShellGl(), touched));
 }
 
 void VrShell::OnPause(JNIEnv* env, const JavaParamRef<jobject>& obj) {
@@ -593,19 +595,24 @@ void VrShell::UpdateGamepadData(device::GvrGamepadData pad) {
 
     unsigned int device_id =
         delegate_provider_->device_provider()->Device()->id();
+
+    // Two gamepad factories: one for screen only, and one for controller.
+    device::GamepadDataFetcherManager::GetInstance()->AddFactory(
+        new device::GvrGamepadDataFetcher::Factory(this, device_id, true));
+
     device::GamepadDataFetcherManager::GetInstance()->AddFactory(

[mthiesse, 2017/05/16 00:44:37]

sidenote, gamepad API is scary :P Add twice, remove once, and magically
everything is fine.

-        new device::GvrGamepadDataFetcher::Factory(this, device_id));
+        new device::GvrGamepadDataFetcher::Factory(this, device_id, false));
     gamepad_source_active_ = true;
   }
-  if (gamepad_data_fetcher_) {
-    gamepad_data_fetcher_->SetGamepadData(pad);
+  for (auto* fetcher : gamepad_data_fetchers_) {
+    fetcher->SetGamepadData(pad);
   }
 }
 
 void VrShell::RegisterGamepadDataFetcher(
     device::GvrGamepadDataFetcher* fetcher) {
   DVLOG(1) << __FUNCTION__ << "(" << fetcher << ")";
-  gamepad_data_fetcher_ = fetcher;
+  gamepad_data_fetchers_.push_back(fetcher);
 }
 
 // ----------------------------------------------------------------------------