**Do you want to request a _feature_ or report a _bug_?**
Enhancement

**What is the current behavior?**
Element type checker is not as informative as the other ones.

**What is the expected behavior?**
It would be nice to provide the actual type of the prop passed similarly to other type checkers. I.e., instead of 

> Invalid prop `Prop` supplied to `Component`, expected a single ReactElement.

say

> Invalid prop `Prop` of type `type` supplied to `Component`, expected a single ReactElement.

**Which versions of React, and which browser / OS are affected by this issue? Did this work in previous versions of React?**
Seeing this on 15.2.1 but I think it's also applicable to previous versions.

I know the general intention is to move away from prop types, but if there isn't a specific reason for the current behavior I can look into making this more pretty.

expectWarningInDevelopment(PropTypes.string.isRequired, 0);
      expectWarningInDevelopment(PropTypes.string.isRequired, 'foo');
      expectWarningInDevelopment(PropTypes.string.isRequired, null);
      expectWarningInDevelopment(PropTypes.string.isRequired, undefined);
      expectWarningInDevelopment(PropTypes.symbol, 0);
      expectWarningInDevelopment(PropTypes.symbol, Symbol('Foo'));
      expectWarningInDevelopment(PropTypes.symbol.isRequired, 0);
      expectWarningInDevelopment(PropTypes.symbol.isRequired, Symbol('Foo'));
      expectWarningInDevelopment(PropTypes.symbol.isRequired, null);
      expectWarningInDevelopment(PropTypes.symbol.isRequired, undefined);
      expectWarningInDevelopment(PropTypes.object, '');
      expectWarningInDevelopment(PropTypes.object, {foo: 'bar'});
      expectWarningInDevelopment(PropTypes.object.isRequired, '');
      expectWarningInDevelopment(PropTypes.object.isRequired, {foo: 'bar'});
      expectWarningInDevelopment(PropTypes.object.isRequired, null);
      expectWarningInDevelopment(PropTypes.object.isRequired, undefined);
    });
  });
  describe('Any type', function() {
    it('should should accept any value', function() {
      typeCheckPass(PropTypes.any, 0);
      typeCheckPass(PropTypes.any, 'str');
      typeCheckPass(PropTypes.any, []);
      typeCheckPass(PropTypes.any, Symbol());
    });
    it('should be implicitly optional and not warn without values', function() {
      typeCheckPass(PropTypes.any, null);
      typeCheckPass(PropTypes.any, undefined);
    });
    it('should warn for missing required values', function() {