get rid of "hiding inherited virtual method" warnings on CanContain() by making it const like it's parent class.

htmlparser/src/COtherDTD.cpp

@@ -362,7 +362,7 @@ nsresult COtherDTD::HandleStyleToken(CToken* aToken){
  *  @param   aChild -- tag enum of child container
  *  @return  PR_TRUE if parent can contain child
  */
-PRBool COtherDTD::CanContain(PRInt32 aParent,PRInt32 aChild) {
+PRBool COtherDTD::CanContain(PRInt32 aParent,PRInt32 aChild) const {
   return CNavDTD::CanContain(aParent,aChild);
 }
 

htmlparser/src/COtherDTD.h

@@ -153,7 +153,7 @@ class COtherDTD : public CNavDTD {
      *  @param   aChild -- int tag of child container
      *  @return  PR_TRUE if parent can contain child
      */
-    virtual PRBool CanContain(PRInt32 aParent,PRInt32 aChild);
+    virtual PRBool CanContain(PRInt32 aParent,PRInt32 aChild) const;
 
     /**
      *  This method is called to determine whether or not a tag

parser/htmlparser/src/COtherDTD.cpp

@@ -362,7 +362,7 @@ nsresult COtherDTD::HandleStyleToken(CToken* aToken){
  *  @param   aChild -- tag enum of child container
  *  @return  PR_TRUE if parent can contain child
  */
-PRBool COtherDTD::CanContain(PRInt32 aParent,PRInt32 aChild) {
+PRBool COtherDTD::CanContain(PRInt32 aParent,PRInt32 aChild) const {
   return CNavDTD::CanContain(aParent,aChild);
 }
 

parser/htmlparser/src/COtherDTD.h

@@ -153,7 +153,7 @@ class COtherDTD : public CNavDTD {
      *  @param   aChild -- int tag of child container
      *  @return  PR_TRUE if parent can contain child
      */
-    virtual PRBool CanContain(PRInt32 aParent,PRInt32 aChild);
+    virtual PRBool CanContain(PRInt32 aParent,PRInt32 aChild) const;
 
     /**
      *  This method is called to determine whether or not a tag