Use all available texture units.

src/gpu/gl/GrGpuGL.h

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 
 #ifndef GrGpuGL_DEFINED
@@ skipping 209 matching lines @@
 
     // flushes the scissor. see the note on flushBoundTextureAndParams about
     // flushing the scissor after that function is called.
     void flushScissor();
 
     void initFSAASupport();
 
     // determines valid stencil formats
     void initStencilFormats();
 
-    void setSpareTextureUnit();
+    // sets a texture unit to use for texture operations other than binding a texture to a program.
+    // ensures that such operations don't negatively interact with tracking bound textures.
+    void setScratchTextureUnit();
 
     // bound is region that may be modified and therefore has to be resolved.
     // NULL means whole target. Can be an empty rect.
     void flushRenderTarget(const GrIRect* bound);
     void flushStencil(DrawType);
     void flushAAState(DrawType);
 
     bool configToGLFormats(GrPixelConfig config,
                            bool getSizedInternal,
                            GrGLenum* internalFormat,
@@ skipping 177 matching lines @@
 
     GrGLProgram::MatrixState    fHWPathStencilMatrixState;
 
     GrStencilSettings           fHWStencilSettings;
     TriState                    fHWStencilTestEnabled;
 
     GrDrawState::DrawFace       fHWDrawFace;
     TriState                    fHWWriteToColor;
     TriState                    fHWDitherEnabled;
     GrRenderTarget*             fHWBoundRenderTarget;
-    GrTexture*                  fHWBoundTextures[GrDrawState::kNumStages];
+    SkTArray<GrTexture*, true>  fHWBoundTextures;
     ///@}
 
     // we record what stencil format worked last time to hopefully exit early
     // from our loop that tries stencil formats and calls check fb status.
     int fLastSuccessfulStencilFmtIdx;
 
     typedef GrGpu INHERITED;
 };
 
 #endif