function checkPropTypes(typeSpecs, values, location, componentName, getStack) {
  if (process.env.NODE_ENV !== 'production') {
    for (var typeSpecName in typeSpecs) {
      if (typeSpecs.hasOwnProperty(typeSpecName)) {
        var error;
        // Prop type validation may throw. In case they do, we don't want to
        // fail the render phase where it didn't fail before. So we log it.
        // After these have been cleaned up, we'll let them throw.
        try {
          // This is intentionally an invariant that gets caught. It's the same
          // behavior as without this statement except with a better message.
          invariant(typeof typeSpecs[typeSpecName] === 'function', '%s: %s type `%s` is invalid; it must be a function, usually from ' + 'the `prop-types` package, but received `%s`.', componentName || 'React class', location, typeSpecName, typeof typeSpecs[typeSpecName]);
          error = typeSpecs[typeSpecName](values, typeSpecName, componentName, location, null, ReactPropTypesSecret);
        } catch (ex) {
          error = ex;
        }
        warning(!error || error instanceof Error, '%s: type specification of %s `%s` is invalid; the type checker ' + 'function must return `null` or an `Error` but returned a %s. ' + 'You may have forgotten to pass an argument to the type checker ' + 'creator (arrayOf, instanceOf, objectOf, oneOf, oneOfType, and ' + 'shape all require an argument).', componentName || 'React class', location, typeSpecName, typeof error);
        if (error instanceof Error && !(error.message in loggedTypeFailures)) {
          // Only monitor this failure once because there tends to be a lot of the
          // same error.
          loggedTypeFailures[error.message] = true;

          var stack = getStack ? getStack() : '';

          warning(false, 'Failed %s type: %s%s', location, error.message, stack != null ? stack : '');
        }
      }
    }
  }
}
Assert that the values match with the type specs.
Error messages are memorized and will only be shown once.

@param {object} typeSpecs Map of name to a ReactPropType
@param {object} values Runtime values that need to be type-checked
@param {string} location e.g. "prop", "context", "child context"
@param {string} componentName Name of the component for error messages.
@param {?Function} getStack Returns the component stack.
@private