Make getElementsByTagName do the right thing with prefixes. Bug 206053,

r=peterv, sr=jst

content/base/public/nsINodeInfo.h

@@ -68,10 +68,10 @@ class nsIURI;
 class nsIPrincipal;
 
 // IID for the nsINodeInfo interface
-// b24fd4ad-7d94-40ea-b09b-9262f58bc28a
+// 37840f19-f65f-4185-baff-c475d9e2b3f2
 #define NS_INODEINFO_IID      \
-{ 0xb24fd4ad, 0x7d94, 0x40ea, \
-  { 0xb0, 0x9b, 0x92, 0x62, 0xf5, 0x8b, 0xc2, 0x8a } }
+{ 0x37840f19, 0xf65f, 0x4185, \
+ { 0xba, 0xff, 0xc4, 0x75, 0xd9, 0xe2, 0xb3, 0xf2 } }
 
 class nsINodeInfo : public nsISupports
 {
@@ -258,8 +258,25 @@ public:
   virtual PRBool Equals(const nsAString& aName, const nsAString& aPrefix,
                         PRInt32 aNamespaceID) const = 0;
   virtual PRBool NamespaceEquals(const nsAString& aNamespaceURI) const = 0;
-  // switch to UTF8 - this allows faster access for consumers
-  virtual PRBool QualifiedNameEquals(const nsACString& aQualifiedName) const = 0;
+
+  PRBool QualifiedNameEquals(nsIAtom* aNameAtom) const
+  {
+    NS_PRECONDITION(aNameAtom, "Must have name atom");
+    if (!GetPrefixAtom())
+      return Equals(aNameAtom);
+
+    const char* utf8;
+    aNameAtom->GetUTF8String(&utf8);
+    return QualifiedNameEqualsInternal(nsDependentCString(utf8));
+  }
+
+  PRBool QualifiedNameEquals(const nsACString& aQualifiedName) const
+  {
+    if (!GetPrefixAtom())
+      return mInner.mName->EqualsUTF8(aQualifiedName);
+
+    return QualifiedNameEqualsInternal(aQualifiedName);    
+  }
 
   /*
    * Retrieve a pointer to the document that owns this node info.
@@ -275,6 +292,9 @@ public:
   virtual nsIPrincipal *GetDocumentPrincipal() const = 0;
 
 protected:
+  virtual PRBool
+    QualifiedNameEqualsInternal(const nsACString& aQualifiedName) const = 0;
+
   /*
    * nsNodeInfoInner is used for two things:
    *

content/base/src/nsContentList.cpp

@@ -717,7 +717,7 @@ nsContentList::Match(nsIContent *aContent)
     nsINodeInfo *ni = aContent->NodeInfo();
 
     if (mMatchNameSpaceId == kNameSpaceID_Unknown) {
-      return (mMatchAll || ni->Equals(mMatchAtom));
+      return (mMatchAll || ni->QualifiedNameEquals(mMatchAtom));
     }
 
     return ((mMatchAll && ni->NamespaceEquals(mMatchNameSpaceId)) ||

content/base/src/nsContentList.h

@@ -169,11 +169,39 @@ class nsContentList : public nsBaseContentList,
 public:
   NS_DECL_ISUPPORTS_INHERITED
 
+  /**
+   * @param aDocument the document to which to add as an nsIDocumentObserver
+   * @param aMatchAtom an atom whose meaning depends on aMatchNameSpaceId
+   * @param aMatchNameSpaceId if kNameSpaceID_Unknown then aMatchAtom is the
+   *                          tagName to match.  Otherwise we match nodes with
+   *                          aMatchNameSpaceId and a localName equal to
+   *                          aMatchAtom
+   * @param aRootContent The content node under which to limit our search.
+   *                     If not null, the root is aDocument.
+   * @param aDeep If false, then look only at children of the root, nothing
+   *              deeper.  If true, then look at the whole subtree rooted at
+   *              our root.
+   */  
   nsContentList(nsIDocument *aDocument, 
                 nsIAtom* aMatchAtom, 
                 PRInt32 aMatchNameSpaceId,
                 nsIContent* aRootContent = nsnull,
                 PRBool aDeep = PR_TRUE);
+
+  /**
+   * @param aDocument the document to which to add as an nsIDocumentObserver
+   * @param aFunc the function to be called to determine whether we match
+   * @param aData a string that will need to be passed back to aFunc
+   * @param aRootContent The content node under which to limit our search.
+   *                     If not null, the root is aDocument.
+   * @param aDeep If false, then look only at children of the root, nothing
+   *              deeper.  If true, then look at the whole subtree rooted at
+   *              our root.
+   * @param aMatchAtom an atom to be passed back to aFunc
+   * @param aMatchNameSpaceId a namespace id to be passed back to aFunc
+   * @param aFuncMayDependOnAttr a boolean that indicates whether this list is
+   *                             sensitive to attribute changes.
+   */  
   nsContentList(nsIDocument *aDocument, 
                 nsContentListMatchFunc aFunc,
                 const nsAString& aData,

content/base/src/nsNodeInfo.cpp

@@ -225,12 +225,10 @@ nsNodeInfo::NamespaceEquals(const nsAString& aNamespaceURI) const
 }
 
 PRBool
-nsNodeInfo::QualifiedNameEquals(const nsACString& aQualifiedName) const
+nsNodeInfo::QualifiedNameEqualsInternal(const nsACString& aQualifiedName) const
 {
+  NS_PRECONDITION(mInner.mPrefix, "Must have prefix");
   
-  if (!mInner.mPrefix)
-    return mInner.mName->EqualsUTF8(aQualifiedName);
-
   nsACString::const_iterator start;
   aQualifiedName.BeginReading(start);
 

content/base/src/nsNodeInfo.h

@@ -66,7 +66,8 @@ public:
   virtual PRBool Equals(const nsAString& aName, const nsAString& aPrefix,
                         PRInt32 aNamespaceID) const;
   virtual PRBool NamespaceEquals(const nsAString& aNamespaceURI) const;
-  virtual PRBool QualifiedNameEquals(const nsACString& aQualifiedName) const;
+  virtual PRBool
+    QualifiedNameEqualsInternal(const nsACString& aQualifiedName) const;
 
   nsIPrincipal *GetDocumentPrincipal() const
   {