[TIMOB-6457] - Exception message processing now returns an appropriat…

…e error message even if the source isn't available

- Change C++-style 'throw' to Obj-C style '@throw'

iphone/Classes/KrollContext.mm

@@ -573,7 +573,8 @@ -(id)invokeWithResult:(KrollContext*)context
 		NSLog(@"[ERROR] Script Error = %@",[TiUtils exceptionMessage:excm]);
 		fflush(stderr);
 		TiStringRelease(js);
-		throw excm;
+
+		@throw excm;
 	}
 
 	TiStringRelease(js);

iphone/Classes/TiUtils.m

@@ -1135,6 +1135,7 @@ +(NSString*)exceptionMessage:(id)arg
 				id lineNumber = [arg objectForKey:@"line"];
 				return [NSString stringWithFormat:@"%@ at %@ (line %@)",message,[source lastPathComponent],lineNumber];
 			}
+            return [NSString stringWithFormat:@"%@ (unknown file)", message];
 		}
 	}
 	return arg;