Capture the columnNumber in FireFox

Author: mattrobenolt

vendor/TraceKit/tracekit.js

@@ -600,6 +600,7 @@ TraceKit.computeStackTrace = (function computeStackTraceWrapper() {
     // ex.message = qq is not defined
     // ex.fileName = http://...
     // ex.lineNumber = 59
+    // ex.columnNumber = 69
     // ex.stack = ...stack trace... (see the example below)
     // ex.name = ReferenceError
     //
@@ -670,14 +671,19 @@ TraceKit.computeStackTrace = (function computeStackTraceWrapper() {
             stack.push(element);
         }
 
-        if (stack[0] && stack[0].line && !stack[0].column && reference) {
-            stack[0].column = findSourceInLine(reference[1], stack[0].url, stack[0].line);
-        }
-
         if (!stack.length) {
             return null;
         }
 
+        if (stack[0].line && !stack[0].column && reference) {
+            stack[0].column = findSourceInLine(reference[1], stack[0].url, stack[0].line);
+        } else if (!stack[0].column && ex.columnNumber) {
+            // FireFox uses this awesome columnNumber property for its top frame
+            // Also note, Firefox's column number is 0-based and everything else expects 1-based,
+            // so adding 1
+            stack[0].column = ex.columnNumber + 1;
+        }
+
         return {
             'mode': 'stack',
             'name': ex.name,