Track texture memory globally

Also mostly consolidates texture creation

Change-Id: Ifea01303afda531dcec99b8fe2a0f64cf2f24420
diff --git a/libs/hwui/font/CacheTexture.h b/libs/hwui/font/CacheTexture.h
index 6dabc76..5510666 100644
--- a/libs/hwui/font/CacheTexture.h
+++ b/libs/hwui/font/CacheTexture.h
@@ -92,11 +92,11 @@
     bool fitBitmap(const SkGlyph& glyph, uint32_t* retOriginX, uint32_t* retOriginY);
 
     inline uint16_t getWidth() const {
-        return mTexture.width;
+        return mWidth;
     }
 
     inline uint16_t getHeight() const {
-        return mTexture.height;
+        return mHeight;
     }
 
     inline GLenum getFormat() const {
@@ -122,7 +122,7 @@
 
     GLuint getTextureId() {
         allocatePixelBuffer();
-        return mTexture.id;
+        return mTexture.id();
     }
 
     inline bool isDirty() const {
@@ -183,6 +183,7 @@
 
     PixelBuffer* mPixelBuffer = nullptr;
     Texture mTexture;
+    uint32_t mWidth, mHeight;
     GLenum mFormat;
     bool mLinearFiltering = false;
     bool mDirty = false;