x11: Split the gfx_x11 target into its own gyp file.

ui/gfx/x/gfx_x11.gyp

+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+{
+  'variables': {
+    'chromium_code': 1,
+    'use_x11': 1,
+  },
+
+  'targets': [
+    {
+      'target_name': 'gfx_x11',
+      'type': '<(component)',
+      'dependencies': [
+        '../../../base/base.gyp:base',
+      ],
+      'defines': [
+        'GFX_IMPLEMENTATION',
+      ],
+      'link_settings': {
+        'libraries': [
+          '-lX11',
+          '-lXi',

[piman, 2014/05/09 21:54:17]

Why not adding a dependency on system.gyp:x11 like it was before?

[sadrul, 2014/05/09 22:11:14]

system.gyp:x11 target is also defined conditionally in system.gyp. So we are
unable to depend on that target when use_x11 is set to off.

If we move the x11 target out of system.gyp into its own separate gyp (e.g.
build/linux/x11.gyp), then this would not be a problem. I can do that if you
think that would be better than this.

+        ],
+      },
+      'sources': [
+        'x11_atom_cache.cc',
+        'x11_atom_cache.h',
+        'x11_connection.cc',
+        'x11_connection.h',
+        'x11_error_tracker.cc',
+        'x11_error_tracker.h',
+        'x11_types.cc',
+        'x11_types.h',
+      ],
+    },
+  ]
+}