Move generic shorthand serialization checks out of specific routines

third_party/WebKit/Source/core/css/StylePropertySerializer.h

Index: third_party/WebKit/Source/core/css/StylePropertySerializer.h
diff --git a/third_party/WebKit/Source/core/css/StylePropertySerializer.h b/third_party/WebKit/Source/core/css/StylePropertySerializer.h
index e075dad4cfa47c85693bf09ecc3cbcfbe6343bb5..cd60e0dab56aa3cf4fe7d0eab7f472d12ba7f206 100644
--- a/third_party/WebKit/Source/core/css/StylePropertySerializer.h
+++ b/third_party/WebKit/Source/core/css/StylePropertySerializer.h
@@ -48,13 +48,20 @@ private:
     String getShorthandValue(const StylePropertyShorthand&, String separator = " ") const;
     String fontValue() const;
     String fontVariantValue() const;
-    void appendFontLonghandValueIfNotNormal(CSSPropertyID, StringBuilder& result, String& value) const;
+    void appendFontLonghandValueIfNotNormal(CSSPropertyID, StringBuilder& result) const;
     String backgroundRepeatPropertyValue() const;
     String getPropertyText(CSSPropertyID, const String& value, bool isImportant, bool isNotFirstDecl) const;
     bool isPropertyShorthandAvailable(const StylePropertyShorthand&) const;
     bool shorthandHasOnlyInitialOrInheritedValue(const StylePropertyShorthand&) const;
     void appendBackgroundPropertyAsText(StringBuilder& result, unsigned& numDecls) const;
 
+    // Valid if all we can serialize to just a css-wide keyword.
+    // Invalid if either some longhands are not set, the important flag not set
+    // consistently, or any css-wide keywords are used.
+    // Unknown otherwise.
+    enum CommonCheckResult { Valid, Invalid, Unknown };
+    CommonCheckResult commonShorthandChecks(const StylePropertyShorthand&, String& result) const;

[alancutter (OOO until 2018), 2016/05/20 01:57:12]

This could return String instead of needing a separate enum, the calling code
can check for isNull() for the equivalent of Unknown.

[Timothy Loh, 2016/05/20 06:10:53]

Done.

+
     // Only StylePropertySerializer uses the following two classes.
     class PropertyValueForSerializer {
         STACK_ALLOCATED();