Use a struct for cc::Surface ids for more type safety

Use a struct for cc::Surface ids for more type safety

We currently represent surface ids as just an int, but may want to move
to a richer data structure in the future. Identifiers that are ints are also
pretty easy to confuse with other ints.

R=piman@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=276923

[jamesr, 2014-06-11 23:13:48]

piman@ - please review

jschuh@ - please review content/common/cc_messages*.  I'm switching an int to a
struct wrapping an int in a data type passed by IPC

https://codereview.chromium.org/331533002/diff/1/cc/DEPS
File cc/DEPS (left):

https://codereview.chromium.org/331533002/diff/1/cc/DEPS#oldcode2
cc/DEPS:2: "-cc/surfaces", # cc shouldn't depend directly on the surface
implementation
needed so cc/layers/surface_layer.h can see surfaceid. I don't think this
restriction is really needed any more

[jschuh, 2014-06-11 23:31:16]

ipc security lgtm

[piman, 2014-06-11 23:48:59]

lgtm

https://codereview.chromium.org/331533002/diff/1/cc/layers/surface_layer.cc
File cc/layers/surface_layer.cc (right):

https://codereview.chromium.org/331533002/diff/1/cc/layers/surface_layer.cc#n...
cc/layers/surface_layer.cc:30: return surface_id_.id != 0 &&
Layer::DrawsContent();
nit: is it worth adding a SurfaceId::is_null()?

https://codereview.chromium.org/331533002/diff/1/cc/layers/surface_layer_impl...
File cc/layers/surface_layer_impl_unittest.cc (right):

https://codereview.chromium.org/331533002/diff/1/cc/layers/surface_layer_impl...
cc/layers/surface_layer_impl_unittest.cc:25: surface_id.id = 9;
nit: add an explicit constructor?

[jamesr, 2014-06-12 21:28:05]

The CQ bit was checked by jamesr@chromium.org

[jamesr, 2014-06-12 21:30:15]

Done and done, thanks.

[commit-bot: I haz the power, 2014-06-12 21:30:17]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/jamesr@chromium.org/331533002/20001

[piman, 2014-06-13 00:48:11]

lgtm

[commit-bot: I haz the power, 2014-06-13 04:20:19]

Change committed as 276923