get genmipmap function in the struct

BUG=
R=bsalomon@google.com, reed@google.com

Author: humper@google.com

Review URL: https://chromiumcodereview.appspot.com/20436002

git-svn-id: http://skia.googlecode.com/svn/trunk@10393 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/include/gpu/GrTexture.h b/include/gpu/GrTexture.h
index a870818..acb7ade 100644
--- a/include/gpu/GrTexture.h
+++ b/include/gpu/GrTexture.h
@@ -43,6 +43,14 @@
     bool isSetFlag(GrTextureFlags flags) const {
         return 0 != (fDesc.fFlags & flags);
     }
+    
+    void dirtyMipMaps(bool mipMapsDirty) {
+        fMipMapsDirty = mipMapsDirty;
+    }
+    
+    bool mipMapsAreDirty() const {
+        return fMipMapsDirty;
+    }
 
     /**
      *  Approximate number of bytes used by the texture
@@ -136,7 +144,8 @@
 
     GrTexture(GrGpu* gpu, bool isWrapped, const GrTextureDesc& desc)
     : INHERITED(gpu, isWrapped, desc)
-    , fRenderTarget(NULL) {
+    , fRenderTarget(NULL) 
+    , fMipMapsDirty(true) {
 
         // only make sense if alloc size is pow2
         fShiftFixedX = 31 - SkCLZ(fDesc.fWidth);
@@ -155,6 +164,8 @@
     // for this texture if the texture is power of two sized.
     int                 fShiftFixedX;
     int                 fShiftFixedY;
+    
+    bool                fMipMapsDirty;
 
     virtual void internal_dispose() const SK_OVERRIDE;