Add a caps bit to enable/disable the new manual mip-mapper

src/gpu/gl/GrGLGpu.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrGLGpu.h"
 #include "GrGLBuffer.h"
 #include "GrGLGLSL.h"
@@ skipping 4296 matching lines @@
                             dstGLRect.fBottom,
                             dstGLRect.fLeft + dstGLRect.fWidth,
                             dstGLRect.fBottom + dstGLRect.fHeight,
                             GR_GL_COLOR_BUFFER_BIT, GR_GL_NEAREST));
     this->unbindTextureFBOForCopy(GR_GL_DRAW_FRAMEBUFFER, dst);
     this->unbindTextureFBOForCopy(GR_GL_READ_FRAMEBUFFER, src);
     this->didWriteToSurface(dst, &dstRect);
     return true;
 }
 
-bool gManualMipmaps = true;
-
 // Manual implementation of mipmap generation, to work around driver bugs w/sRGB.
 // Uses draw calls to do a series of downsample operations to successive mips.
 // If this returns false, then the calling code falls back to using glGenerateMipmap.
 bool GrGLGpu::generateMipmap(GrGLTexture* texture, bool gammaCorrect) {
-    // Global switch for manual mipmap generation:
-    if (!gManualMipmaps) {
+    // Our iterative downsample requires the ability to limit which level we're sampling:
+    if (!this->glCaps().doManualMipmapping()) {
         return false;
     }
 
     // Mipmaps are only supported on 2D textures:
     if (GR_GL_TEXTURE_2D != texture->target()) {
         return false;
     }
 
     // We need to be able to render to the texture for this to work:
     if (!this->caps()->isConfigRenderable(texture->config(), false)) {
         return false;
     }
 
-    // Our iterative downsample requires the ability to limit which level we're sampling:
-    if (!this->glCaps().mipMapLevelAndLodControlSupport()) {
-        return false;
-    }
-
     // If we're mipping an sRGB texture, we need to ensure FB sRGB is correct:
     if (GrPixelConfigIsSRGB(texture->config())) {
         // If we have write-control, just set the state that we want:
         if (this->glCaps().srgbWriteControl()) {
             this->flushFramebufferSRGB(gammaCorrect);
         } else if (!gammaCorrect) {
             // If we don't have write-control we can't do non-gamma-correct mipmapping:
             return false;
         }
     }
@@ skipping 294 matching lines @@
         if (GR_GL_TEXTURE_EXTERNAL == glTexture->target() ||
             GR_GL_TEXTURE_RECTANGLE == glTexture->target()) {
             copyParams->fFilter = GrTextureParams::kNone_FilterMode;
             copyParams->fWidth = texture->width();
             copyParams->fHeight = texture->height();
             return true;
         }
     }
     return false;
 }