Clean unused parameters, disable warnings

Change-Id: Iddb872f53075dd022eeef45265594d1c6a9e2bc0
diff --git a/libs/hwui/TextureCache.cpp b/libs/hwui/TextureCache.cpp
index ed0a79a..a56eb33 100644
--- a/libs/hwui/TextureCache.cpp
+++ b/libs/hwui/TextureCache.cpp
@@ -103,7 +103,7 @@
 // Callbacks
 ///////////////////////////////////////////////////////////////////////////////
 
-void TextureCache::operator()(SkBitmap*& bitmap, Texture*& texture) {
+void TextureCache::operator()(SkBitmap*&, Texture*& texture) {
     // This will be called already locked
     if (texture) {
         mSize -= texture->bitmapSize;