Custom Error Test

• Crucial and failed tests are marked FAIL. Non-crucial failed tests are marked "no".
• Err_inherits uses util.inherits which is supported only in Node.
• class and extends are not supported by all browsers. See compatibility table.
• Object.setPrototypeOf() is not supported by all browsers. See compatibility table.
• See console for stack samples of each custom error.
• Click on the headers to view each implementation code.