Introducing TOOLKIT_USES_PURE_VIEWS

As per oshima:

The ultimate goal is to eliminate TOOLKIT_USES_GTK. Once that migration is completed, TOOLKIT_VIEWS + OS_LINUX should be enough.

Until this happens, we need a binary that:
1) has both gtk and pure-views
2) can enable pure views components with --use-pure-views when possible (this is default in touchui=1). 

If we could switch everything with --use-pure-views, that'd be nice, but the world is not perfect and there are things that cannot co-exist (such as message pump). For such component, we'll use GYP_DEFINES to switch.

1) TOOLKIT_USES_PURE_VIEWS is defined with toolkit_pure_views=1.
2) all (or most of) chrome features must be functional with toolkit_pure_views=1
3) both TOOLKIT_USES_GTK and TOOLKIT_USES_PURE_VIEWS are defined. The latter has higher priority (that is, if implementation can't co-exists, TOOLKIT_USE_PURE_VIEWS will take precedence).
4) As the migration proceeds, there will be less TOOLKIT_USES_GTK and more TOOLKIT_USES_PURE_VIEWS.
5) Once the migration is complete (that is, there is no TOOKIT_USES_GTK), we can remove TOOLKIT_USES_PURE_VIEWS or replace it with OS_LINUX when necessary.

BUG=none
TEST=none

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=91164

[oshima, 2011-06-30 00:06:32]

http://codereview.chromium.org/7273079/diff/1/build/common.gypi
File build/common.gypi (right):

http://codereview.chromium.org/7273079/diff/1/build/common.gypi#newcode24
build/common.gypi:24: # Whether the Views toolkit is Pure or GTK
Please add comment that this is an intermediate solution and will be removed
once migration is completed.

http://codereview.chromium.org/7273079/diff/1/build/common.gypi#newcode25
build/common.gypi:25: 'toolkit_pure_views%': 0,
toolkit_uses_pure_views would be better.

http://codereview.chromium.org/7273079/diff/1/views/widget/widget.cc
File views/widget/widget.cc (right):

http://codereview.chromium.org/7273079/diff/1/views/widget/widget.cc#newcode199
views/widget/widget.cc:199: #if defined(TOOLKIT_USES_PURE_VIEWS)
this should be "defined(TOUCH_UI)"

[Emmanuel Saint-loubert-Bié, 2011-06-30 00:23:29]

Oshima PTAL

http://codereview.chromium.org/7273079/diff/1/build/common.gypi
File build/common.gypi (right):

http://codereview.chromium.org/7273079/diff/1/build/common.gypi#newcode24
build/common.gypi:24: # Whether the Views toolkit is Pure or GTK
On 2011/06/30 00:06:32, oshima wrote:
> Please add comment that this is an intermediate solution and will be removed
> once migration is completed.

Done.

http://codereview.chromium.org/7273079/diff/1/build/common.gypi#newcode25
build/common.gypi:25: 'toolkit_pure_views%': 0,
On 2011/06/30 00:06:32, oshima wrote:
> toolkit_uses_pure_views would be better.

Done.

http://codereview.chromium.org/7273079/diff/1/views/widget/widget.cc
File views/widget/widget.cc (right):

http://codereview.chromium.org/7273079/diff/1/views/widget/widget.cc#newcode199
views/widget/widget.cc:199: #if defined(TOOLKIT_USES_PURE_VIEWS)
On 2011/06/30 00:06:32, oshima wrote:
> this should be "defined(TOUCH_UI)"

Done.

[oshima, 2011-06-30 17:46:51]

Can you update the comment? then LGTM.

http://codereview.chromium.org/7273079/diff/1006/build/common.gypi
File build/common.gypi (right):

http://codereview.chromium.org/7273079/diff/1006/build/common.gypi#newcode29
build/common.gypi:29: # the remaining GTK code (which will diminish over time).
Can you incorporate something like below?

TOOLKIT_USES_PURE_VIEWS macro is used to replace corresponding GTK
implementation in such a way that GTK and PureViews can coexist. This
intermediate solution allow us to switch the
view implementations using --use-pure-views, without breaking exiting gtk
implementation.