Split bindings/v8/custom into core and modules.

Source/core/core.gyp

Index: Source/core/core.gyp
diff --git a/Source/core/core.gyp b/Source/core/core.gyp
index 1d6d0c620653127b571bb555ba9d579ded1b187a..8022dfe9994c48a917f24788368d310c1c5da66f 100644
--- a/Source/core/core.gyp
+++ b/Source/core/core.gyp
@@ -45,7 +45,7 @@
       # FIXME: Remove the following two lines once core scripts generate qualified
       # includes correctly: http://crbug.com/380054
       '<(bindings_core_v8_output_dir)',
-      '<(bindings_modules_v8_output_dir)',
+      '<(bindings_modules_v8_output_dir)', # e.g. EventTargetCustom requires.

[Nils Barth (inactive), 2014/06/24 03:14:02]

You mean EventHeaders.h (gen/blink/core),
not V8EventTargetCustom.cpp (Source/bindings/[core/]v8);
it's *core* build scripts that are the problems:
bindings all have correctly qualified includes.

Could you fix this and also move it up so it's above the dir lines?

[tasak, 2014/06/24 10:55:45]

I mean, EventTargetCustom.cpp's toV8 depends on
modules/EventTargetModulesHeaders because of 
EVENT_TARGET_MODULES_INTERFACES_FOR_EACH(TRY_TO_WRAP_WITH_INTERFACE).

I think, this means, core's toV8 depends on some modules.

I have to split the toV8 into core version and modules' version.
As far as I understand, core can depend on bindings' core. So
bindings_core_v8_output_dir looks correct, but bindings_modules_v8_output_dir
looks wrong.
I moved up bindings_core_v8_output_dir line and updated the comment.

[Nils Barth (inactive), 2014/06/25 01:37:40]

*V8*EventTargetCustom.cpp.
That's a good point, and something that needs fixing,
but that's not what's happening here.

This is "include dirs", and these lines are only necessary
due to *unqualified* includes.
(We're qualifying includes exactly so we can track dependencies,
as you're noticing.)

For example, the include lines for
V8EventTargetCustom.cpp
are:
#include "core/EventTargetHeaders.h"
#include "core/EventTargetInterfaces.h"
#include "modules/EventTargetModulesHeaders.h"
#include "modules/EventTargetModulesInterfaces.h"

All the includes are qualified (relative to Source or gen/blink),
so V8EventTargetCustom.cpp does *not* need
gen/blink/bindings/core/v8
gen/blink/bindings/modules/v8
in its include search path.

However, EventHeaders.h starts with:
#include "core/events/KeyboardEvent.h"
#include "V8KeyboardEvent.h"
...and the second line is an *unqualified* include, which should read:
#include "bindings/core/v8/V8KeyboardEvent.h"

That's why these include_dir lines are there, and that's why
I was correcting your comment.

This is what Chang was doing in:
Add sub-directories to the include lines of generated files.
https://code.google.com/p/chromium/issues/detail?id=381876
*bindings_core*
You're right about dependencies, but *include dirs* should not
be used.
That ensures that include paths are properly qualified,
and thus we can use checkdeps to validate *dependencies*
(which is what we really care about).
https://code.google.com/p/chromium/issues/detail?id=365190


So here's the idea:
1. Make core properly qualify include paths.
2. Remove these include_dir lines (this guarantees that include paths are
properly qualified).
3. Run checkdeps on gen/blink.
4. It fails because
gen/blink/bindings/core/v8/V8EventTargetCustom.cpp
has
#include "modules/EventTargetModulesHeaders.h"
...and bindings_core is not allowed to depend on modules.

[tasak, 2014/06/25 12:33:34]

Thank you. I see. I probably understand what are issues. The original comment is
correct.
I've just reverted my change.

       '<(SHARED_INTERMEDIATE_DIR)/blink',  # gen/blink
     ],