Fix for bugs

1312   - Mapped all  HTML 4.0x FPIs to NOQUIRKS mode.
2749   - Tweaked strict comment handling code. -> r=rickg
17148 - Making sure that BeginContext() is ended only by EndContext()
17113, 1262 - Made AddLeaf(), in DTD,  to be cautious in handling text tokens.

Using bit-wise search  for IsContainer() instead of looping. ( nsElementTable )

Fixed warnings.

r=pollmann

parser/htmlparser/src/nsHTMLTokens.cpp

@@ -729,7 +729,7 @@ nsresult ConsumeStrictComment(PRUnichar aChar, nsScanner& aScanner,nsString& aSt
           if(kMinus==aChar) {
                //in this case, we're reading a long-form comment <-- xxx -->
             aString+=aChar;
-            result=aScanner.ReadWhile(aString,gMinus,PR_TRUE,PR_FALSE);  //get all available '---'
+            //result=aScanner.ReadWhile(aString,gMinus,PR_TRUE,PR_FALSE);  //get all available '---'
             if(NS_OK==result) {
               PRInt32 findpos=-1;
               nsAutoString temp("");