removed calls to deprecated string methods

layout/mathml/base/src/nsMathMLContainerFrame.cpp

@@ -197,7 +197,7 @@ nsMathMLContainerFrame::ParseNumericValue(nsString&   aString,
       return PR_FALSE;  // two dots encountered
     else if (c == '.')
       gotDot = PR_TRUE;
-    else if (!nsString::IsDigit(c)) {
+    else if (!nsCRT::IsAsciiDigit(c)) {
       aString.Right(unit, stringLength - i);
       break;
     }

mailnews/compose/src/nsMsgCompUtils.cpp

@@ -1033,7 +1033,7 @@ msg_generate_message_id (nsIMsgIdentity *identity)
 		if (host) {
 			const char *s;
 			for (s = ++host; *s; s++)
-				if (!nsCRT::IsAsciiAlpha(*s) && !nsString::IsDigit(*s) &&
+        if (!nsCRT::IsAsciiAlpha(*s) && !nsCRT::IsAsciiDigit(*s) &&
 						*s != '-' && *s != '_' && *s != '.') {
 					host = 0;
 					break;

netwerk/base/src/nsProtocolProxyService.cpp

@@ -167,7 +167,7 @@ nsProtocolProxyService::CanUseProxy(nsIURI* aURI)
         PRInt32 nport = 0; // no proxy port
         // find the end of this element. 
         while (*endproxy && (*endproxy != ',' && 
-                    !nsString::IsSpace(*endproxy)))
+          !nsCRT::IsAsciiSpace(*endproxy)))
         {
             if (*endproxy == ':')
                 portLocation=endproxy;

rdf/base/src/nsRDFContentSink.cpp

@@ -1038,7 +1038,7 @@ RDFContentSinkImpl::GetIdAboutAttribute(const nsIParserNode& aNode,
             // mean http://www.w3.org/TR/REC-xml#NT-Letter, which it
             // probably isn't.
             PRUnichar first = name.First();
-            if (! nsString::IsAlpha(first) &&
+            if (! nsCRT::IsAsciiAlpha(first) &&
                 first != PRUnichar(':') &&
                 first != PRUnichar('_')) {
                 PR_LOG(gLog, PR_LOG_ALWAYS,