Track texture memory globally

Also mostly consolidates texture creation

Change-Id: Ifea01303afda531dcec99b8fe2a0f64cf2f24420
diff --git a/libs/hwui/font/CacheTexture.cpp b/libs/hwui/font/CacheTexture.cpp
index d2685da..8ba4761 100644
--- a/libs/hwui/font/CacheTexture.cpp
+++ b/libs/hwui/font/CacheTexture.cpp
@@ -111,11 +111,11 @@
 
 CacheTexture::CacheTexture(uint16_t width, uint16_t height, GLenum format, uint32_t maxQuadCount)
         : mTexture(Caches::getInstance())
+        , mWidth(width)
+        , mHeight(height)
         , mFormat(format)
         , mMaxQuadCount(maxQuadCount)
         , mCaches(Caches::getInstance()) {
-    mTexture.width = width;
-    mTexture.height = height;
     mTexture.blend = true;
 
     mCacheBlocks = new CacheBlock(TEXTURE_BORDER_SIZE, TEXTURE_BORDER_SIZE,
@@ -160,10 +160,7 @@
         delete mPixelBuffer;
         mPixelBuffer = nullptr;
     }
-    if (mTexture.id) {
-        mCaches.textureState().deleteTexture(mTexture.id);
-        mTexture.id = 0;
-    }
+    mTexture.deleteTexture();
     mDirty = false;
     mCurrentQuad = 0;
 }
@@ -183,22 +180,9 @@
         mPixelBuffer = PixelBuffer::create(mFormat, getWidth(), getHeight());
     }
 
-    if (!mTexture.id) {
-        glGenTextures(1, &mTexture.id);
-
-        mCaches.textureState().bindTexture(mTexture.id);
-        glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
-        // Initialize texture dimensions
-        glTexImage2D(GL_TEXTURE_2D, 0, mFormat, getWidth(), getHeight(), 0,
-                mFormat, GL_UNSIGNED_BYTE, nullptr);
-
-        const GLenum filtering = getLinearFiltering() ? GL_LINEAR : GL_NEAREST;
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, filtering);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, filtering);
-
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
-    }
+    mTexture.resize(mWidth, mHeight, mFormat);
+    mTexture.setFilter(getLinearFiltering() ? GL_LINEAR : GL_NEAREST);
+    mTexture.setWrap(GL_CLAMP_TO_EDGE);
 }
 
 bool CacheTexture::upload() {