Add GN buildfiles for ui/compositor and snapshot.

Add GN buildfiles for ui/compositor and snapshot.

Rename "//ui/base:ui_base" to "//ui/base:base" to make it easier to specify

BUG=
R=jamesr@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=273883

[jamesr, 2014-05-30 03:32:09]

What is the criteria you are using for static_library vs source_set?

https://codereview.chromium.org/306113002/diff/1/ui/compositor/BUILD.gn
File ui/compositor/BUILD.gn (right):

https://codereview.chromium.org/306113002/diff/1/ui/compositor/BUILD.gn#newco...
ui/compositor/BUILD.gn:73: source_set("test_support") {
why a source_set instead of a static lib target? what's the difference here?

https://codereview.chromium.org/306113002/diff/1/ui/snapshot/BUILD.gn
File ui/snapshot/BUILD.gn (right):

https://codereview.chromium.org/306113002/diff/1/ui/snapshot/BUILD.gn#newcode82
ui/snapshot/BUILD.gn:82: source_set("test_support") {
why source_set?

[brettw, 2014-05-30 05:22:48]

There's also some discussion here about this:
https://code.google.com/p/chromium/wiki/GNCookbook
(I just added on in response to your questions)

https://codereview.chromium.org/306113002/diff/1/ui/snapshot/BUILD.gn
File ui/snapshot/BUILD.gn (right):

https://codereview.chromium.org/306113002/diff/1/ui/snapshot/BUILD.gn#newcode82
ui/snapshot/BUILD.gn:82: source_set("test_support") {
Always use source set instead of static library. The only time you should use
static library is when you're producing something to ship (we do this in a few
places for exporting stuff).

Mixing static libraries and source sets can lead to confusing linker errors. I
have a patch to remove the few static_libraries we have floating around.

[jamesr, 2014-05-30 19:13:22]

lgtm

[jamesr, 2014-05-30 19:14:05]

I fixed a typo ADd->Add in the title/description - if you land by hand you might
need to do that locally too (maybe?)

[brettw, 2014-05-30 19:22:01]

I think it takes the description from Reitveld. Let's find out!

[brettw, 2014-05-30 19:22:02]

I think it takes the description from Reitveld. Let's find out!

[brettw, 2014-05-30 19:22:45]

Committed patchset #2 manually as r273883.

[brettw, 2014-05-30 19:23:38]

On 2014/05/30 19:22:02, brettw wrote:
> I think it takes the description from Reitveld. Let's find out!

Yes, it does.