cc: Fix masks when the RenderPassDrawQuad does not cover the whole pass

cc/output/gl_renderer.cc

 // Copyright 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/output/gl_renderer.h"
 
 #include <algorithm>
 #include <limits>
 #include <set>
 #include <string>
@@ skipping 993 matching lines @@
     DCHECK_NE(shader_mask_tex_coord_offset_location, 1);
     GLC(Context(), Context()->uniform1i(shader_mask_sampler_location, 1));
 
     float mask_tex_scale_x = quad->mask_uv_rect.width() / tex_scale_x;
     float mask_tex_scale_y = quad->mask_uv_rect.height() / tex_scale_y;
 
     // Mask textures are oriented vertically flipped relative to the framebuffer
     // and the RenderPass contents texture, so we flip the tex coords from the
     // RenderPass texture to find the mask texture coords.
     GLC(Context(),
-        Context()->uniform2f(shader_mask_tex_coord_offset_location,
-                             quad->mask_uv_rect.x(),
-                             quad->mask_uv_rect.y() + mask_tex_scale_y));
+        Context()->uniform2f(
+            shader_mask_tex_coord_offset_location,
+            quad->mask_uv_rect.x(),
+            quad->mask_uv_rect.y() + quad->mask_uv_rect.height()));
     GLC(Context(),
         Context()->uniform2f(shader_mask_tex_coord_scale_location,
                              mask_tex_scale_x,
                              -mask_tex_scale_y));
     shader_mask_sampler_lock = make_scoped_ptr(
         new ResourceProvider::ScopedSamplerGL(resource_provider_,
                                               quad->mask_resource_id,
                                               GL_TEXTURE_2D,
                                               GL_TEXTURE1,
                                               GL_LINEAR));
@@ skipping 2061 matching lines @@
   // The Skia GPU backend requires a stencil buffer.  See ReinitializeGrCanvas
   // implementation.
   return gr_context_ && context_->getContextAttributes().stencil;
 }
 
 bool GLRenderer::IsContextLost() {
   return (context_->getGraphicsResetStatusARB() != GL_NO_ERROR);
 }
 
 }  // namespace cc