Fix Caches singleton to avoid resource leaks

The declaration of Singleton objects must be in CPP files (not header
files) to avoid creating separate instances of what is supposedly a
single object.

Change-Id: Ie903384824a458b5572f3ce5b6cfb359c18a9c44
diff --git a/libs/hwui/Caches.cpp b/libs/hwui/Caches.cpp
new file mode 100644
index 0000000..a4def0b
--- /dev/null
+++ b/libs/hwui/Caches.cpp
@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2010 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.
+ */
+
+#define LOG_TAG "OpenGLRenderer"
+
+#include "Caches.h"
+
+namespace android {
+
+#ifdef USE_OPENGL_RENDERER
+using namespace uirenderer;
+ANDROID_SINGLETON_STATIC_INSTANCE(Caches);
+#endif
+
+namespace uirenderer {
+
+///////////////////////////////////////////////////////////////////////////////
+// Constructors/destructor
+///////////////////////////////////////////////////////////////////////////////
+
+Caches::Caches(): Singleton<Caches>(), blend(false), lastSrcMode(GL_ZERO),
+        lastDstMode(GL_ZERO), currentProgram(NULL) {
+    GLint maxTextureUnits;
+    glGetIntegerv(GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS, &maxTextureUnits);
+    if (maxTextureUnits < REQUIRED_TEXTURE_UNITS_COUNT) {
+        LOGW("At least %d texture units are required!", REQUIRED_TEXTURE_UNITS_COUNT);
+    }
+
+    glGenBuffers(1, &meshBuffer);
+    glBindBuffer(GL_ARRAY_BUFFER, meshBuffer);
+    glBufferData(GL_ARRAY_BUFFER, sizeof(gMeshVertices), gMeshVertices, GL_STATIC_DRAW);
+
+    currentBuffer = meshBuffer;
+}
+
+/**
+ * Binds the VBO used to render simple textured quads.
+ */
+void Caches::bindMeshBuffer() {
+    bindMeshBuffer(meshBuffer);
+}
+
+/**
+ * Binds the specified VBO.
+ */
+void Caches::bindMeshBuffer(const GLuint buffer) {
+    if (currentBuffer != buffer) {
+        glBindBuffer(GL_ARRAY_BUFFER, buffer);
+        currentBuffer = buffer;
+    }
+}
+
+/**
+ * Unbinds the VBO used to render simple textured quads.
+ */
+void Caches::unbindMeshBuffer() {
+    if (currentBuffer) {
+        glBindBuffer(GL_ARRAY_BUFFER, 0);
+        currentBuffer = 0;
+    }
+}
+
+}; // namespace uirenderer
+}; // namespace android