fix: gracefully handle read-only "column"-property of the Error class

- this is the case in Safari starting with version 9.0
- see 07511e0
- also see #1285

Author: nknapp

lib/handlebars/exception.js

@@ -19,13 +19,28 @@ function Exception(message, node) {
     this[errorProps[idx]] = tmp[errorProps[idx]];
   }
 
+  /* istanbul ignore else */
   if (Error.captureStackTrace) {
     Error.captureStackTrace(this, Exception);
   }
 
-  if (loc) {
-    this.lineNumber = line;
-    this.column = column;
+  try {
+    if (loc) {
+      this.lineNumber = line;
+
+      // Work around issue under safari where we can't directly set the column value
+      /* istanbul ignore next */
+      if (Object.defineProperty) {
+        Object.defineProperty(this, 'column', {
+          value: column,
+          enumerable: true
+        });
+      } else {
+        this.column = column;
+      }
+    }
+  } catch (nop) {
+    /* Ignore if the browser is very particular */
   }
 }