Expose Gamepad API instance for Cardboard button

chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellImpl.java

Index: chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellImpl.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellImpl.java b/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellImpl.java
index aff70783ec833767b94a72b89916cdf694855b6e..98f9dcb5b269da59ecc00d5b59c096649471fbf2 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellImpl.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellImpl.java
@@ -230,7 +230,13 @@ public class VrShellImpl
             public boolean onTouch(View v, MotionEvent event) {
                 if (!CommandLine.getInstance().hasSwitch(ChromeSwitches.ENABLE_VR_SHELL_DEV)

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

I think you can remove the switch checks. onTouch should only be called when
paired with a cardboard, even if the view is touched, so we should
unconditionally call OnTrigger.

As mentioned below we should just remove this old workaround.

                         && event.getActionMasked() == MotionEvent.ACTION_DOWN) {
-                    nativeOnTriggerEvent(mNativeVrShell);
+                    nativeOnTriggerEvent(mNativeVrShell, true);
+                    return true;
+                }
+                if (!CommandLine.getInstance().hasSwitch(ChromeSwitches.ENABLE_VR_SHELL_DEV)
+                        && (event.getActionMasked() == MotionEvent.ACTION_UP
+                                   || event.getActionMasked() == MotionEvent.ACTION_CANCEL)) {
+                    nativeOnTriggerEvent(mNativeVrShell, false);
                     return true;
                 }
                 return false;
@@ -405,8 +411,12 @@ public class VrShellImpl
         boolean cardboardTriggered = false;
         if (CommandLine.getInstance().hasSwitch(ChromeSwitches.ENABLE_VR_SHELL_DEV)
                 && event.getActionMasked() == MotionEvent.ACTION_DOWN) {
-            nativeOnTriggerEvent(mNativeVrShell);
+            nativeOnTriggerEvent(mNativeVrShell, true);
             cardboardTriggered = true;
+        } else if (CommandLine.getInstance().hasSwitch(ChromeSwitches.ENABLE_VR_SHELL_DEV)
+                && (event.getActionMasked() == MotionEvent.ACTION_UP
+                           || event.getActionMasked() == MotionEvent.ACTION_CANCEL)) {
+            nativeOnTriggerEvent(mNativeVrShell, false);
         }
         boolean parentConsumed = super.dispatchTouchEvent(event);
         if (mOnDispatchTouchEventForTesting != null) {
@@ -605,7 +615,7 @@ public class VrShellImpl
     private native void nativeSwapContents(
             long nativeVrShell, WebContents webContents, MotionEventSynthesizer eventSynthesizer);
     private native void nativeDestroy(long nativeVrShell);
-    private native void nativeOnTriggerEvent(long nativeVrShell);
+    private native void nativeOnTriggerEvent(long nativeVrShell, boolean touched);
     private native void nativeOnPause(long nativeVrShell);
     private native void nativeOnResume(long nativeVrShell);
     private native void nativeOnLoadProgressChanged(long nativeVrShell, double progress);