Disallow LCD text for layers under normal filter.

Disallows LCD text if the effect node has normal filter operations.
This CL simply checks only the intermediate node.

Bug: 1074521
Change-Id: I6e9caec484599fa47e1649356e9762ca265bee22
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2312059Reviewed-by: Xianzhu Wang <wangxianzhu@chromium.org>
Commit-Queue: jongdeok.kim <jongdeok.kim@navercorp.com>
Cr-Commit-Position: refs/heads/master@{#791698}

cc/debug/debug_colors.cc

@@ -339,6 +339,8 @@ SkColor DebugColors::NonLCDTextHighlightColor(LCDTextDisallowedReason reason) {
       return SkColorSetARGB(96, 255, 0, 128);
     case LCDTextDisallowedReason::kWillChangeTransform:
       return SkColorSetARGB(96, 128, 0, 255);
+    case LCDTextDisallowedReason::kLayerHasFilterEffect:
+      return SkColorSetARGB(96, 0, 128, 0);
   }
   NOTREACHED();
   return SK_ColorTRANSPARENT;

cc/layers/picture_layer_impl.cc

@@ -863,6 +863,11 @@ LCDTextDisallowedReason PictureLayerImpl::ComputeLCDTextDisallowedReason()
   if (has_will_change_transform_hint())
     return LCDTextDisallowedReason::kWillChangeTransform;
 
+  EffectNode* effect_node = GetEffectTree().Node(effect_tree_index());
+  // TODO(crbug.com/1074521): Should also consider ancestor filters.
+  if (!effect_node->filters.IsEmpty())
+    return LCDTextDisallowedReason::kLayerHasFilterEffect;
+
   return LCDTextDisallowedReason::kNone;
 }
 

cc/raster/lcd_text_disallowed_reason.cc

@@ -27,6 +27,8 @@ const char* LCDTextDisallowedReasonToString(LCDTextDisallowedReason reason) {
       return "non-integral-y-offset";
     case LCDTextDisallowedReason::kWillChangeTransform:
       return "will-change-transform";
+    case LCDTextDisallowedReason::kLayerHasFilterEffect:
+      return "layer-has-filter-effect";
   }
   NOTREACHED();
   return "";

cc/raster/lcd_text_disallowed_reason.h

@@ -24,7 +24,8 @@ enum class LCDTextDisallowedReason : uint8_t {
   kNonIntegralXOffset = 5,
   kNonIntegralYOffset = 6,
   kWillChangeTransform = 7,
-  kMaxValue = kWillChangeTransform,
+  kLayerHasFilterEffect = 8,
+  kMaxValue = kLayerHasFilterEffect,
 };
 constexpr size_t kLCDTextDisallowedReasonCount =
     static_cast<size_t>(LCDTextDisallowedReason::kMaxValue) + 1;

cc/trees/draw_properties_unittest.cc

@@ -3791,6 +3791,18 @@ TEST_P(LCDTextTest, CanUseLCDText) {
   CheckCanUseLCDText(LCDTextDisallowedReason::kWillChangeTransform, child_);
   // TODO(wangxianzhu): Is this correct?
   CheckCanUseLCDText(LCDTextDisallowedReason::kNone, grand_child_);
+
+  // Case 12: Sanity check: restore will-change: transform.
+  child_->SetHasWillChangeTransformHint(false);
+  UpdateActiveTreeDrawProperties();
+  CheckCanUseLCDText(LCDTextDisallowedReason::kNone);
+
+  // Case 13: Normal filter.
+  FilterOperations blur_filter;
+  blur_filter.Append(FilterOperation::CreateBlurFilter(4.0f));
+  SetFilter(child_, blur_filter);
+  UpdateActiveTreeDrawProperties();
+  CheckCanUseLCDText(LCDTextDisallowedReason::kLayerHasFilterEffect, child_);
 }
 
 TEST_P(LCDTextTest, CanUseLCDTextWithContentsOpaqueForText) {