Intercept WebVR api calls and check for VrCore compatibility.

chrome/browser/android/vr_shell/vr_shell_delegate.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_delegate.h"
 
 #include <utility>
 
 #include "base/android/jni_android.h"
 #include "chrome/browser/android/vr_shell/non_presenting_gvr_delegate.h"
@@ skipping 107 matching lines @@
   }
 }
 
 void VrShellDelegate::ShowTab(int id) {
   JNIEnv* env = AttachCurrentThread();
   Java_VrShellDelegate_showTab(env, j_vr_shell_delegate_.obj(), id);
 }
 
 void VrShellDelegate::SetDeviceProvider(
     device::GvrDeviceProvider* device_provider) {
+  JNIEnv* env = AttachCurrentThread();
+  bool vrCorecompatible = static_cast<bool>(
+      Java_VrShellDelegate_isVrCoreCompatible(env, j_vr_shell_delegate_.obj()));
+  if (!vrCorecompatible)
+    return;
+
   CHECK(!device_provider_);
   device_provider_ = device_provider;
   if (!delegate_)
     CreateNonPresentingDelegate();
   device_provider_->Device()->OnDelegateChanged();
 }
 
 void VrShellDelegate::ClearDeviceProvider() {
-  non_presenting_delegate_ = nullptr;
-  JNIEnv* env = AttachCurrentThread();
-  Java_VrShellDelegate_shutdownNonPresentingNativeContext(
-      env, j_vr_shell_delegate_.obj());
-  device_provider_->Device()->OnDelegateChanged();
+  // Clean up the non-presenting delegate.
+  if (non_presenting_delegate_) {
+    non_presenting_delegate_ = nullptr;
+    JNIEnv* env = AttachCurrentThread();
+    Java_VrShellDelegate_shutdownNonPresentingNativeContext(
+        env, j_vr_shell_delegate_.obj());
+    device_provider_->Device()->OnDelegateChanged();
+  }
   device_provider_ = nullptr;
 }
 
 void VrShellDelegate::RequestWebVRPresent(
     const base::Callback<void(bool)>& callback) {
   if (!present_callback_.is_null()) {
     // Can only handle one request at a time. This is also extremely unlikely to
     // happen in practice.
     callback.Run(false);
     return;
@@ skipping 54 matching lines @@
 
 bool RegisterVrShellDelegate(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
 jlong Init(JNIEnv* env, const JavaParamRef<jobject>& obj) {
   return reinterpret_cast<intptr_t>(new VrShellDelegate(env, obj));
 }
 
 }  // namespace vr_shell