Bug 1345804 part 2 - Add new AtomIdent unit to nsCSSValue. r=heycam

MozReview-Commit-ID: 4Qc3POvHrJg

--HG--
extra : rebase_source : 80b4ca720db36d47fc0b9e69bd6c4f03de758ce2

layout/style/nsCSSValue.cpp

@@ -226,6 +226,10 @@ nsCSSValue::nsCSSValue(const nsCSSValue& aCopy)
     mValue.mFontFamilyList = aCopy.mValue.mFontFamilyList;
     mValue.mFontFamilyList->AddRef();
   }
+  else if (eCSSUnit_AtomIdent == mUnit) {
+    mValue.mAtom = aCopy.mValue.mAtom;
+    mValue.mAtom->AddRef();
+  }
   else {
     MOZ_ASSERT(false, "unknown unit");
   }
@@ -321,6 +325,9 @@ bool nsCSSValue::operator==(const nsCSSValue& aOther) const
     else if (eCSSUnit_FontFamilyList == mUnit) {
       return *mValue.mFontFamilyList == *aOther.mValue.mFontFamilyList;
     }
+    else if (eCSSUnit_AtomIdent == mUnit) {
+      return mValue.mAtom == aOther.mValue.mAtom;
+    }
     else {
       return mValue.mFloat == aOther.mValue.mFloat;
     }
@@ -453,6 +460,8 @@ void nsCSSValue::DoReset()
     DO_RELEASE(mGridTemplateAreas);
   } else if (eCSSUnit_FontFamilyList == mUnit) {
     DO_RELEASE(mFontFamilyList);
+  } else if (eCSSUnit_AtomIdent == mUnit) {
+    DO_RELEASE(mAtom);
   }
   mUnit = eCSSUnit_Null;
 }
@@ -975,6 +984,16 @@ nsCSSValue::BufferFromString(const nsString& aValue)
   return buffer.forget();
 }
 
+void
+nsCSSValue::AtomizeIdentValue()
+{
+  MOZ_ASSERT(mUnit == eCSSUnit_Ident);
+  nsCOMPtr<nsIAtom> atom = NS_Atomize(GetStringBufferValue());
+  Reset();
+  mUnit = eCSSUnit_AtomIdent;
+  mValue.mAtom = atom.forget().take();
+}
+
 namespace {
 
 struct CSSValueSerializeCalcOps {
@@ -1966,6 +1985,9 @@ nsCSSValue::AppendToString(nsCSSPropertyID aProperty, nsAString& aResult,
   } else if (eCSSUnit_FontFamilyList == unit) {
     nsStyleUtil::AppendEscapedCSSFontFamilyList(*mValue.mFontFamilyList,
                                                 aResult);
+  } else if (eCSSUnit_AtomIdent == unit) {
+    nsDependentAtomString buffer(GetAtomValue());
+    nsStyleUtil::AppendEscapedCSSIdent(buffer, aResult);
   }
 
   switch (unit) {
@@ -1986,6 +2008,7 @@ nsCSSValue::AppendToString(nsCSSPropertyID aProperty, nsAString& aResult,
     case eCSSUnit_FontFamilyList: break;
     case eCSSUnit_String:       break;
     case eCSSUnit_Ident:        break;
+    case eCSSUnit_AtomIdent:    break;
     case eCSSUnit_URL:          break;
     case eCSSUnit_Image:        break;
     case eCSSUnit_Element:      break;
@@ -2183,6 +2206,10 @@ nsCSSValue::SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const
       n += mValue.mFontFamilyList->SizeOfIncludingThis(aMallocSizeOf);
       break;
 
+    // Atom is always shared, and thus should not be counted.
+    case eCSSUnit_AtomIdent:
+      break;
+
     // Int: nothing extra to measure.
     case eCSSUnit_Integer:
     case eCSSUnit_Enumerated:

layout/style/nsCSSValue.h

@@ -34,6 +34,7 @@
 #include <type_traits>
 
 class imgRequestProxy;
+class nsIAtom;
 class nsIContent;
 class nsIDocument;
 class nsIPrincipal;
@@ -491,6 +492,9 @@ enum nsCSSUnit {
 
   eCSSUnit_FontFamilyList = 58,   // (FontFamilyList*) value
 
+  // Atom units
+  eCSSUnit_AtomIdent    = 60,     // (nsIAtom*) for its string as an identifier
+
   eCSSUnit_Integer      = 70,     // (int) simple value
   eCSSUnit_Enumerated   = 71,     // (int) value has enumerated meaning
 
@@ -880,6 +884,11 @@ public:
     return mValue.mFloatColor;
   }
 
+  nsIAtom* GetAtomValue() const {
+    MOZ_ASSERT(mUnit == eCSSUnit_AtomIdent);
+    return mValue.mAtom;
+  }
+
   void Reset()  // sets to null
   {
     if (mUnit != eCSSUnit_Null)
@@ -964,6 +973,9 @@ public:
   static already_AddRefed<nsStringBuffer>
     BufferFromString(const nsString& aValue);
 
+  // Convert the given Ident value into AtomIdent.
+  void AtomizeIdentValue();
+
   size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;
 
   static void
@@ -1008,6 +1020,7 @@ protected:
     // If we're of a string type, mString is not null.
     nsStringBuffer* MOZ_OWNING_REF mString;
     nscolor    mColor;
+    nsIAtom* MOZ_OWNING_REF mAtom;
     Array* MOZ_OWNING_REF mArray;
     mozilla::css::URLValue* MOZ_OWNING_REF mURL;
     mozilla::css::ImageValue* MOZ_OWNING_REF mImage;