Allow multiple post-resolve callbacks. (Maybe not the long term approach for CSS transitions, but easiest right now.) (Bug 435441) r=bzbarsky

layout/style/nsHTMLStyleSheet.cpp

@@ -205,7 +205,7 @@ nsHTMLStyleSheet::TableTbodyRule::MapRuleInfoInto(nsRuleData* aRuleData)
 {
   if (aRuleData->mSIDs & NS_STYLE_INHERIT_BIT(Border)) {
     aRuleData->mCanStoreInRuleTree = PR_FALSE;
-    aRuleData->mPostResolveCallback = &TbodyPostResolveCallback;
+    aRuleData->mPostResolveCallbacks.AppendElement(&TbodyPostResolveCallback);
   }
   return NS_OK;
 }
@@ -224,7 +224,7 @@ nsHTMLStyleSheet::TableRowRule::MapRuleInfoInto(nsRuleData* aRuleData)
 {
   if (aRuleData->mSIDs & NS_STYLE_INHERIT_BIT(Border)) {
     aRuleData->mCanStoreInRuleTree = PR_FALSE;
-    aRuleData->mPostResolveCallback = &RowPostResolveCallback;
+    aRuleData->mPostResolveCallbacks.AppendElement(&RowPostResolveCallback);
   }
   return NS_OK;
 }
@@ -242,7 +242,7 @@ nsHTMLStyleSheet::TableColgroupRule::MapRuleInfoInto(nsRuleData* aRuleData)
 {
   if (aRuleData->mSIDs & NS_STYLE_INHERIT_BIT(Border)) {
     aRuleData->mCanStoreInRuleTree = PR_FALSE;
-    aRuleData->mPostResolveCallback = &ColgroupPostResolveCallback;
+    aRuleData->mPostResolveCallbacks.AppendElement(&ColgroupPostResolveCallback);
   }
   return NS_OK;
 }
@@ -271,7 +271,7 @@ nsHTMLStyleSheet::TableColRule::MapRuleInfoInto(nsRuleData* aRuleData)
 {
   if (aRuleData->mSIDs & NS_STYLE_INHERIT_BIT(Border)) {
     aRuleData->mCanStoreInRuleTree = PR_FALSE;
-    aRuleData->mPostResolveCallback = &ColPostResolveCallback;
+    aRuleData->mPostResolveCallbacks.AppendElement(&ColPostResolveCallback);
   }
   return NS_OK;
 }
@@ -281,7 +281,7 @@ nsHTMLStyleSheet::TableUngroupedColRule::MapRuleInfoInto(nsRuleData* aRuleData)
 {
   if (aRuleData->mSIDs & NS_STYLE_INHERIT_BIT(Border)) {
     aRuleData->mCanStoreInRuleTree = PR_FALSE;
-    aRuleData->mPostResolveCallback = &UngroupedColPostResolveCallback;
+    aRuleData->mPostResolveCallbacks.AppendElement(&UngroupedColPostResolveCallback);
   }
   return NS_OK;
 }

layout/style/nsRuleData.h

@@ -46,6 +46,7 @@
 
 #include "nsCSSStruct.h"
 #include "nsStyleStructFwd.h"
+#include "nsTArray.h"
 class nsPresContext;
 class nsStyleContext;
 
@@ -60,7 +61,9 @@ struct nsRuleData
   PRUint8 mLevel; // an nsStyleSet::sheetType
   nsPresContext* mPresContext;
   nsStyleContext* mStyleContext;
-  nsPostResolveFunc mPostResolveCallback;
+  // MapRuleInfoInto should append to this array, so it is ordered from
+  // most specific to least.
+  nsTArray<nsPostResolveFunc> mPostResolveCallbacks;
   nsRuleDataFont* mFontData; // Should always be stack-allocated! We don't own these structures!
   nsRuleDataDisplay* mDisplayData;
   nsRuleDataMargin* mMarginData;
@@ -80,7 +83,7 @@ struct nsRuleData
   nsRuleDataColumn* mColumnData;
 
   nsRuleData(PRUint32 aSIDs, nsPresContext* aContext, nsStyleContext* aStyleContext) 
-    :mSIDs(aSIDs), mPresContext(aContext), mStyleContext(aStyleContext), mPostResolveCallback(nsnull),
+    :mSIDs(aSIDs), mPresContext(aContext), mStyleContext(aStyleContext),
      mFontData(nsnull), mDisplayData(nsnull), mMarginData(nsnull), mListData(nsnull), 
      mPositionData(nsnull), mTableData(nsnull), mColorData(nsnull), mContentData(nsnull), mTextData(nsnull),
      mUserInterfaceData(nsnull), mColumnData(nsnull)

layout/style/nsRuleNode.cpp

@@ -1944,7 +1944,8 @@ nsRuleNode::WalkRuleTree(const nsStyleStructID aSID,
     detail = eRulePartialMixed; // Treat as though some data is specified to avoid
                                 // the optimizations and force data computation.
 
-  if (detail == eRuleNone && startStruct && !aRuleData->mPostResolveCallback) {
+  if (detail == eRuleNone && startStruct &&
+      aRuleData->mPostResolveCallbacks.IsEmpty()) {
     // We specified absolutely no rule information, but a parent rule in the tree
     // specified all the rule information.  We set a bit along the branch from our
     // node in the tree to the node that specified the data that tells nodes on that
@@ -1953,7 +1954,7 @@ nsRuleNode::WalkRuleTree(const nsStyleStructID aSID,
     PropagateDependentBit(bit, ruleNode);
     return startStruct;
   }
-  // FIXME Do we need to check for mPostResolveCallback?
+  // FIXME Do we need to check for mPostResolveCallbacks?
   if ((!startStruct && !isReset &&
        (detail == eRuleNone || detail == eRulePartialInherited)) ||
       detail == eRuleFullInherited) {
@@ -2008,9 +2009,13 @@ nsRuleNode::WalkRuleTree(const nsStyleStructID aSID,
 #undef STYLE_STRUCT
 #undef STYLE_STRUCT_TEST
 
-  // If we have a post-resolve callback, handle that now.
-  if (aRuleData->mPostResolveCallback && (NS_LIKELY(res != nsnull)))
-    (*aRuleData->mPostResolveCallback)(const_cast<void*>(res), aRuleData);
+  // If we have post-resolve callbacks, handle that now.
+  if (NS_LIKELY(res != nsnull)) {
+    // Enumerate from least to most specific rule.
+    for (PRUint32 i = aRuleData->mPostResolveCallbacks.Length(); i-- != 0; ) {
+      (*aRuleData->mPostResolveCallbacks[i])(const_cast<void*>(res), aRuleData);
+    }
+  }
 
   // Now return the result.
   return res;
@@ -3003,9 +3008,11 @@ nsRuleNode::SetGenericFont(nsPresContext* aPresContext,
                         PR_FALSE, dummy);
 
     // XXX Not sure if we need to do this here
-    // If we have a post-resolve callback, handle that now.
-    if (ruleData.mPostResolveCallback)
-      (ruleData.mPostResolveCallback)(aFont, &ruleData);
+    // If we have post-resolve callbacks, handle that now.
+    // Enumerate from least to most specific rule.
+    for (PRUint32 j = ruleData.mPostResolveCallbacks.Length(); j-- != 0; ) {
+      (*ruleData.mPostResolveCallbacks[j])(aFont, &ruleData);
+    }
 
     parentFont = *aFont;
   }