cc: Stop using magic numbers to detect if we can use partial updates.

cc/trees/layer_tree_host_unittest.cc

 // Copyright 2011 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/trees/layer_tree_host.h"
 
 #include <algorithm>
 
 #include "base/auto_reset.h"
 #include "base/synchronization/lock.h"
@@ skipping 1465 matching lines @@
         // Number of textures should be one for each layer.
         ASSERT_EQ(2u, context->NumTextures());
         // Number of textures used for commit should be one for each layer.
         EXPECT_EQ(2u, context->NumUsedTextures());
         // Verify that used textures are correct.
         EXPECT_TRUE(context->UsedTexture(context->TextureAt(0)));
         EXPECT_TRUE(context->UsedTexture(context->TextureAt(1)));
         context->ResetUsedTextures();
         break;
       case 1:
-        // Number of textures should be two for each content layer.
-        ASSERT_EQ(4u, context->NumTextures());
+        if (HasImplThread()) {
+          // Number of textures should be two for each content layer.
+          ASSERT_EQ(4u, context->NumTextures());
+        } else {
+          // In single thread we can always do partial updates, so the limit has
+          // no effect.
+          ASSERT_EQ(2u, context->NumTextures());
+        }
         // Number of textures used for commit should be one for each content
         // layer.
         EXPECT_EQ(2u, context->NumUsedTextures());
 
-        // First content textures should not have been used.
-        EXPECT_FALSE(context->UsedTexture(context->TextureAt(0)));
-        EXPECT_FALSE(context->UsedTexture(context->TextureAt(1)));
-        // New textures should have been used.
-        EXPECT_TRUE(context->UsedTexture(context->TextureAt(2)));
-        EXPECT_TRUE(context->UsedTexture(context->TextureAt(3)));
+        if (HasImplThread()) {
+          // First content textures should not have been used.
+          EXPECT_FALSE(context->UsedTexture(context->TextureAt(0)));
+          EXPECT_FALSE(context->UsedTexture(context->TextureAt(1)));
+          // New textures should have been used.
+          EXPECT_TRUE(context->UsedTexture(context->TextureAt(2)));
+          EXPECT_TRUE(context->UsedTexture(context->TextureAt(3)));
+        } else {
+          // In single thread we can always do partial updates, so the limit has
+          // no effect.
+          EXPECT_TRUE(context->UsedTexture(context->TextureAt(0)));
+          EXPECT_TRUE(context->UsedTexture(context->TextureAt(1)));
+        }
 
         context->ResetUsedTextures();
         break;
       case 2:
-        // Number of textures should be two for each content layer.
-        ASSERT_EQ(4u, context->NumTextures());
+        if (HasImplThread()) {
+          // Number of textures should be two for each content layer.
+          ASSERT_EQ(4u, context->NumTextures());
+        } else {
+          // In single thread we can always do partial updates, so the limit has
+          // no effect.
+          ASSERT_EQ(2u, context->NumTextures());
+        }
         // Number of textures used for commit should be one for each content
         // layer.
         EXPECT_EQ(2u, context->NumUsedTextures());
 
-        // One content layer does a partial update also.
-        EXPECT_TRUE(context->UsedTexture(context->TextureAt(2)));
-        EXPECT_FALSE(context->UsedTexture(context->TextureAt(3)));
+        if (HasImplThread()) {
+          // One content layer does a partial update also.
+          EXPECT_TRUE(context->UsedTexture(context->TextureAt(2)));
+          EXPECT_FALSE(context->UsedTexture(context->TextureAt(3)));
+        } else {
+          // In single thread we can always do partial updates, so the limit has
+          // no effect.
+          EXPECT_TRUE(context->UsedTexture(context->TextureAt(0)));
+          EXPECT_TRUE(context->UsedTexture(context->TextureAt(1)));
+        }
 
         context->ResetUsedTextures();
         break;
       case 3:
         // No textures should be used for commit.
         EXPECT_EQ(0u, context->NumUsedTextures());
 
         context->ResetUsedTextures();
         break;
       case 4:
@@ skipping 3315 matching lines @@
     : public LayerTreeHostTestOffscreenContext {
  protected:
   LayerTreeHostTestOffscreenContext_WithContext() { with_context_ = true; }
 };
 
 SINGLE_AND_MULTI_THREAD_TEST_F(LayerTreeHostTestOffscreenContext_WithContext);
 
 }  // namespace
 
 }  // namespace cc