add DeviceInfo

This reverts commit 096895550b9d5430d7a001d491566decf4f9791b.

Change-Id: Ib2ed1e96d8f7f88302f5e27fe735687194553104
diff --git a/libs/hwui/DeviceInfo.cpp b/libs/hwui/DeviceInfo.cpp
new file mode 100644
index 0000000..03b1706
--- /dev/null
+++ b/libs/hwui/DeviceInfo.cpp
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include <DeviceInfo.h>
+
+#include "Extensions.h"
+
+#include <GLES2/gl2.h>
+
+#include <thread>
+#include <mutex>
+
+namespace android {
+namespace uirenderer {
+
+static DeviceInfo* sDeviceInfo = nullptr;
+static std::once_flag sInitializedFlag;
+
+const DeviceInfo* DeviceInfo::get() {
+    return sDeviceInfo;
+}
+
+void DeviceInfo::initialize() {
+    std::call_once(sInitializedFlag, []() {
+        sDeviceInfo = new DeviceInfo();
+        sDeviceInfo->load();
+    });
+}
+
+void DeviceInfo::load() {
+    mExtensions.load();
+    glGetIntegerv(GL_MAX_TEXTURE_SIZE, &mMaxTextureSize);
+}
+
+} /* namespace uirenderer */
+} /* namespace android */