Introduce ChromeVR to Chrome on Android (behind a build flag)

chrome/browser/android/vr_shell/BUILD.gn

+# 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.
+
+import("//build/config/android/rules.gni")
+import("//chrome/common/features.gni")
+
+assert(enable_vr_shell && android_java_ui)
+
+static_library("vr_shell") {
+  sources = [
+    "vr_shell.cc",
+    "vr_shell.h",
+    "vr_shell_renderer.cc",
+    "vr_shell_renderer.h",
+    "vr_util.cc",
+    "vr_util.h",
+  ]
+
+  deps = [
+    ":vr_shell_jni_headers",
+    "//base",
+    "//third_party/gvr-android-sdk:gvr_base_java",
+    "//third_party/gvr-android-sdk:gvr_common_java",
+    "//third_party/gvr-android-sdk:libgvr",
+    "//ui/gl",
+    "//ui/gl/init",
+  ]
+
+  configs += [ "//third_party/gvr-android-sdk:libgvr_config" ]
+}
+
+generate_jni("vr_shell_jni_headers") {
+  sources = [
+    "//chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShell.java",
+  ]
+  jni_package = "vr_shell"
+}