Bug 1424120 - Part 4: Remove haveValue logic from ToInteger. r=njn

The `haveValue` logic is no longer necessary. If we don't have a value the
result will always be 0.

--HG--
extra : rebase_source : df79cbe1dab86914873de72f0ef8fe72d3469e1a

xpcom/string/nsTStringObsolete.cpp

@@ -169,13 +169,10 @@ ToIntegerCommon(const nsTString<T>& aSrc,
       *aErrorCode = NS_OK;
 
       //now iterate the numeric chars and build our result
-      bool haveValue = false;
-
       while(cp<endcp){
         theChar=*cp++;
         if(('0'<=theChar) && (theChar<='9')){
           result = (aRadix * result) + (theChar-'0');
-          haveValue = true;
         }
         else if((theChar>='A') && (theChar<='F')) {
           if(10==aRadix) {
@@ -185,7 +182,6 @@ ToIntegerCommon(const nsTString<T>& aSrc,
           }
           else {
             result = (aRadix * result) + ((theChar-'A')+10);
-            haveValue = true;
           }
         }
         else if((theChar>='a') && (theChar<='f')) {
@@ -196,10 +192,9 @@ ToIntegerCommon(const nsTString<T>& aSrc,
           }
           else {
             result = (aRadix * result) + ((theChar-'a')+10);
-            haveValue = true;
           }
         }
-        else if((('X'==theChar) || ('x'==theChar)) && (!haveValue || result == 0)) {
+        else if((('X'==theChar) || ('x'==theChar)) && result == 0) {
           // For some reason we support a leading 'x' regardless of radix. For
           // example: "000000x500", aRadix = 10 would be parsed as 500 rather
           // than 0.