Add a way to query GL extensions.

Change-Id: Ic27dbf72289dacf641b640a749fbd40c12cd474f
diff --git a/libs/hwui/TextureCache.cpp b/libs/hwui/TextureCache.cpp
index ff9e2aff..4975edb 100644
--- a/libs/hwui/TextureCache.cpp
+++ b/libs/hwui/TextureCache.cpp
@@ -128,6 +128,11 @@
     glPixelStorei(GL_UNPACK_ALIGNMENT, bitmap->bytesPerPixel());
 
     switch (bitmap->getConfig()) {
+    case SkBitmap::kA8_Config:
+        texture->blend = true;
+        glTexImage2D(GL_TEXTURE_2D, 0, GL_ALPHA, bitmap->rowBytesAsPixels(), texture->height, 0,
+                GL_ALPHA, GL_UNSIGNED_BYTE, bitmap->getPixels());
+        break;
     case SkBitmap::kRGB_565_Config:
         texture->blend = false;
         glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, bitmap->rowBytesAsPixels(), texture->height, 0,