Function: isSelector(string)

Description: Checks if a string consists of a valid CSS selector.

Returns: True if yes, False otherwise.

Note: The isSelector() function does not support chaining.

Example:

// Check if a string consists of a valid CSS selector.

var isSelector = $A.isSelector('This is a test.'); // Returns false

var isSelector = $A.isSelector('*[role="tablist"]'); // Returns true