Adds filter support for offscreen canvas

third_party/WebKit/Source/core/style/ComputedStyle.h

Index: third_party/WebKit/Source/core/style/ComputedStyle.h
diff --git a/third_party/WebKit/Source/core/style/ComputedStyle.h b/third_party/WebKit/Source/core/style/ComputedStyle.h
index a3f659a41fe1b3f9ff0251d9893730b1ff95ac0c..4599ef51fc2f6a888c06bb0d67f00391827c269e 100644
--- a/third_party/WebKit/Source/core/style/ComputedStyle.h
+++ b/third_party/WebKit/Source/core/style/ComputedStyle.h
@@ -383,20 +383,25 @@ protected:
 
 private:
     // TODO(sashab): Move these to the bottom of ComputedStyle.
-    ALWAYS_INLINE ComputedStyle();
+    ComputedStyle();
 
     enum InitialStyleTag {
         InitialStyle
     };
-    ALWAYS_INLINE explicit ComputedStyle(InitialStyleTag);
-    ALWAYS_INLINE ComputedStyle(const ComputedStyle&);
+    explicit ComputedStyle(InitialStyleTag);
+    ComputedStyle(const ComputedStyle&);
 
     static PassRefPtr<ComputedStyle> createInitialStyle();
-    static inline ComputedStyle& mutableInitialStyle()
+    static ComputedStyle& mutableInitialStyle()
     {
         LEAK_SANITIZER_DISABLED_SCOPE;
-        DEFINE_STATIC_REF(ComputedStyle, s_initialStyle, (ComputedStyle::createInitialStyle()));
-        return *s_initialStyle;
+
+        DEFINE_THREAD_SAFE_STATIC_LOCAL(ThreadSpecific<ComputedStyle*>, s_initialStyle,
+            new ThreadSpecific<ComputedStyle*>());

[esprehn, 2016/09/12 20:53:12]

Can't put TLS here, it's too slow

+        if (!*s_initialStyle) {
+            *s_initialStyle = PassRefPtr<ComputedStyle>(ComputedStyle::createInitialStyle()).leakRef();
+        }
+        return **s_initialStyle;
     }
 
 public: