[Fiber] Set DOM attributes

[gaearon]

This builds on top of #7941 and adds basic support for setting DOM attributes.
Commit for review: 5a5bb86.

Test plan: examples/fiber/index.html now can put className on a div:

examples/basic/index.html still works both with regular and minified builds.

There were a couple of issues:

• I needed DOMProperty so I had to inject ReactDefaultInjection which brought a bunch of the non-Fiber renderer into the Fiber build. I don't see a simpler workaround right now because we want to keep tests that test ReactDOMFiber alongside non-Fibery ReactDOMServer. Those are tricky to fix if we let both ReactDOMFiber and ReactDOMServer inject their own stuff independently. Another plausible option is to completely fork the files but it seemed excessive.
• I had to decouple DOMPropertyOperations from ReactDOMComponentTree so I added an explicit debugID argument to all methods.

This PR does include not support for events, web components, or style attribute. I figured I wouldn't waste time on this unless we agreed the approach is correct.

Fiber before this PR:

Test Suites: 73 failed, 46 passed, 119 total
Tests:       712 failed, 3 skipped, 736 passed, 1451 total

Fiber after this PR:

Test Suites: 73 failed, 46 passed, 119 total
Tests:       690 failed, 3 skipped, 758 passed, 1451 total

[iamdustan]

I was under the impression that Injection was going to go away with Fiber (not sure the exact implications for how much of the DOM renderer would need to be rewritten or forked)

[gaearon]

Longer term that would be great IMO but shorter term we need to as many tests passing as possible while we simultaneously maintain both reconcilers.

I don't care much either way, and I could just copy and paste those files and give them different names.

[sebmarkbage]

Some of the event system and DOM properties injection will remain for now. However, you don't need them to implement a generic renderer.

[gaearon]

Rebased.

[iamdustan]

Trying to understand how some things work, it looks like the ReactDOMComponentTree logic was hoisted out of ReactDOMProperties as a stepping stone to this TODO.

If I understand correctly: had this change not hoisted ReactDOMComponentTree out of the (set|delete)ValueForProperty calls the tests would fail. With this change a subset of the tests and functionality pass, though the ReactPerf and ReactDevtools would still not be able to take advantage of this.

Is this an okay-ish understanding or am I off?

[gaearon]

This is right. (I also was the person who put that DOMComponentTree thing into DOMOperations during ReactPerf rewrite because I was too lazy to pass debugID explicitly and now it's my time to pay for this.)

[gaearon]

Per discussion, we'll fix small things (like composite tests wanting className) on a case by case basis, and then do a big pass for DOM/events stuff.