cc: Remove code for drawing checkerboard quads, it's not used.

cc/output/gl_renderer.cc

Index: cc/output/gl_renderer.cc
diff --git a/cc/output/gl_renderer.cc b/cc/output/gl_renderer.cc
index 3ffc676a66d18bced61279012515b50aa7ea7df0..a89c33d140c8eab3123b0ae65c0b3a6aaa344f50 100644
--- a/cc/output/gl_renderer.cc
+++ b/cc/output/gl_renderer.cc
@@ -518,10 +518,6 @@ void GLRenderer::DoDrawQuad(DrawingFrame* frame,
     case DrawQuad::INVALID:
       NOTREACHED();
       break;
-    case DrawQuad::CHECKERBOARD:
-      DrawCheckerboardQuad(frame, CheckerboardDrawQuad::MaterialCast(quad),
-                           clip_region);
-      break;
     case DrawQuad::DEBUG_BORDER:
       DrawDebugBorderQuad(frame, DebugBorderDrawQuad::MaterialCast(quad));
       break;
@@ -564,48 +560,6 @@ void GLRenderer::DoDrawQuad(DrawingFrame* frame,
   }
 }
 
-void GLRenderer::DrawCheckerboardQuad(const DrawingFrame* frame,
-                                      const CheckerboardDrawQuad* quad,
-                                      const gfx::QuadF* clip_region) {
-  // TODO(enne) For now since checkerboards shouldn't be part of a 3D
-  // context, clipping regions aren't supported so we skip drawing them
-  // if this becomes the case.
-  if (clip_region) {
-    return;
-  }
-  SetBlendEnabled(quad->ShouldDrawWithBlending());
-
-  const TileCheckerboardProgram* program = GetTileCheckerboardProgram();
-  DCHECK(program && (program->initialized() || IsContextLost()));
-  SetUseProgram(program->program());
-
-  SkColor color = quad->color;
-  gl_->Uniform4f(program->fragment_shader().color_location(),
-                 SkColorGetR(color) * (1.0f / 255.0f),
-                 SkColorGetG(color) * (1.0f / 255.0f),
-                 SkColorGetB(color) * (1.0f / 255.0f), 1);
-
-  const int kCheckerboardWidth = 16;
-  float frequency = 1.0f / kCheckerboardWidth;
-
-  gfx::Rect tile_rect = quad->rect;
-  float tex_offset_x =
-      static_cast<int>(tile_rect.x() / quad->scale) % kCheckerboardWidth;
-  float tex_offset_y =
-      static_cast<int>(tile_rect.y() / quad->scale) % kCheckerboardWidth;
-  float tex_scale_x = tile_rect.width() / quad->scale;
-  float tex_scale_y = tile_rect.height() / quad->scale;
-  gl_->Uniform4f(program->fragment_shader().tex_transform_location(),
-                 tex_offset_x, tex_offset_y, tex_scale_x, tex_scale_y);
-
-  gl_->Uniform1f(program->fragment_shader().frequency_location(), frequency);
-
-  SetShaderOpacity(quad->shared_quad_state->opacity,
-                   program->fragment_shader().alpha_location());
-  DrawQuadGeometry(frame, quad->shared_quad_state->quad_to_target_transform,
-                   quad->rect, program->vertex_shader().matrix_location());
-}
-
 // This function does not handle 3D sorting right now, since the debug border
 // quads are just drawn as their original quads and not in split pieces. This
 // results in some debug border quads drawing over foreground quads.
@@ -3027,17 +2981,6 @@ void GLRenderer::PrepareGeometry(BoundGeometry binding) {
   bound_geometry_ = binding;
 }
 
-const GLRenderer::TileCheckerboardProgram*
-GLRenderer::GetTileCheckerboardProgram() {
-  if (!tile_checkerboard_program_.initialized()) {
-    TRACE_EVENT0("cc", "GLRenderer::checkerboardProgram::initalize");
-    tile_checkerboard_program_.Initialize(output_surface_->context_provider(),
-                                          TEX_COORD_PRECISION_NA,
-                                          SAMPLER_TYPE_NA);
-  }
-  return &tile_checkerboard_program_;
-}
-
 const GLRenderer::DebugBorderProgram* GLRenderer::GetDebugBorderProgram() {
   if (!debug_border_program_.initialized()) {
     TRACE_EVENT0("cc", "GLRenderer::debugBorderProgram::initialize");
@@ -3499,8 +3442,6 @@ void GLRenderer::CleanupSharedObjects() {
     video_stream_texture_program_[i].Cleanup(gl_);
   }
 
-  tile_checkerboard_program_.Cleanup(gl_);
-
   debug_border_program_.Cleanup(gl_);
   solid_color_program_.Cleanup(gl_);
   solid_color_program_aa_.Cleanup(gl_);