Do not always use X11 for Linux builds, inherit Chromium's settings

BUILD.gn

@@ -2,6 +2,9 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+# import the use_x11 variable
+import("//build/config/ui.gni")
+
 gles_gypi = exec_script(
   "//build/gypi_to_gn.py",
   [ rebase_path("src/libGLESv2.gypi") ],
@@ -197,6 +200,9 @@ config("libANGLE_config") {
   if (angle_enable_gl) {
     defines += [ "ANGLE_ENABLE_OPENGL" ]
   }
+  if (use_x11) {
+    defines += [ "ANGLE_USE_X11" ]
+  }
   defines += [
     "GL_APICALL=",
     "GL_GLEXT_PROTOTYPES=",
@@ -244,7 +250,7 @@ static_library("libANGLE") {
     if (is_win) {
       sources += rebase_path(gles_gypi.libangle_gl_wgl_sources, ".", "src")
     }
-    if (is_linux) {
+    if (use_x11) {
       sources += rebase_path(gles_gypi.libangle_gl_glx_sources, ".", "src")
       libs += [ "X11" ]
     }

build/common_defines.gypi

@@ -9,6 +9,15 @@
         'windows_sdk_path%': 'C:/Program Files (x86)/Windows Kits/8.1',
         'angle_build_winrt%': '0',
         'angle_build_winphone%': '0',
+        'angle_build_winrt_app_type_revision%': '8.1',
+        'use_x11%': 0,
+        'conditions':
+        [
+            ['OS=="linux"',
+            {
+                'use_x11%': 1,
+            }],
+        ],
     },
     'msvs_disabled_warnings':
     [
@@ -20,7 +29,7 @@
 
         # TODO: 4702 doesn't fire on xtree in VS2015 (CTP6). We can remove C4702 after moving to VS2015.
         4702, # Unreachable code. Should only fire on system header xtree.
-        
+
         4718, # Recursive call has no side effects. Fires on xtree too.
     ],
     'conditions':

samples/samples.gyp

@@ -47,16 +47,6 @@
                 'sample_util/tga_utils.cpp',
                 'sample_util/tga_utils.h',
             ],
-            'conditions':
-            [
-                ['OS=="linux"',
-                {
-                    'ldflags':
-                    [
-                        '-lX11'
-                    ],
-                }],
-            ],
             'msvs_disabled_warnings': [ 4201 ],
             'direct_dependent_settings':
             {

src/libANGLE/Display.cpp

@@ -35,7 +35,7 @@
 #if defined(ANGLE_ENABLE_OPENGL)
 #   if defined(ANGLE_PLATFORM_WINDOWS)
 #       include "libANGLE/renderer/gl/wgl/DisplayWGL.h"
-#   elif defined(ANGLE_PLATFORM_LINUX)
+#   elif defined(ANGLE_USE_X11)
 #       include "libANGLE/renderer/gl/glx/DisplayGLX.h"
 #   else
 #       error Unsupported OpenGL platform.
@@ -109,7 +109,7 @@ rx::DisplayImpl *CreateDisplayImpl(const AttributeMap &attribMap)
 #if defined(ANGLE_ENABLE_D3D9) || defined(ANGLE_ENABLE_D3D11)
         // Default to D3D displays
         impl = new rx::DisplayD3D();
-#elif defined(ANGLE_PLATFORM_LINUX)
+#elif defined(ANGLE_USE_X11)
         impl = new rx::DisplayGLX();
 #else
         // No display available
@@ -131,7 +131,7 @@ rx::DisplayImpl *CreateDisplayImpl(const AttributeMap &attribMap)
 #if defined(ANGLE_ENABLE_OPENGL)
 #if defined(ANGLE_PLATFORM_WINDOWS)
         impl = new rx::DisplayWGL();
-#elif defined(ANGLE_PLATFORM_LINUX)
+#elif defined(ANGLE_USE_X11)
         impl = new rx::DisplayGLX();
 #else
 #error Unsupported OpenGL platform.

src/libGLESv2.gypi

@@ -547,6 +547,13 @@
                             'ANGLE_ENABLE_OPENGL',
                         ],
                     }],
+                    ['use_x11==1',
+                    {
+                        'defines':
+                        [
+                            'ANGLE_USE_X11',
+                        ]
+                    }],
                 ],
             },
             'conditions':
@@ -656,7 +663,7 @@
                                 '<@(libangle_gl_wgl_sources)',
                             ],
                         }],
-                        ['OS=="linux"',
+                        ['use_x11==1',
                         {
                             'sources':
                             [
@@ -665,6 +672,13 @@
                         }],
                     ],
                 }],
+                ['use_x11==1',
+                {
+                    'defines':
+                    [
+                        'ANGLE_USE_X11',
+                    ]
+                }],
                 ['angle_build_winrt==0 and OS=="win"',
                 {
                     'dependencies':
@@ -744,7 +758,7 @@
                 {
                     'msvs_enable_winphone' : '1',
                 }],
-                ['OS=="linux"',
+                ['use_x11==1',
                 {
                     'link_settings': {
                         'ldflags': [

util/util.gyp

@@ -35,9 +35,12 @@
             'linux/Linux_path_utils.cpp',
             'linux/LinuxTimer.cpp',
             'linux/LinuxTimer.h',
+        ],
+        'util_x11_sources':
+        [
             'x11/X11Window.cpp',
             'x11/X11Window.h',
-        ]
+        ],
     },
     'targets':
     [
@@ -88,6 +91,13 @@
                     [
                         '<@(util_linux_sources)',
                     ],
+                }],
+                ['use_x11==1',
+                {
+                    'sources':
+                    [
+                        '<@(util_x11_sources)',
+                    ],
                     'link_settings': {
                         'ldflags': [
                             '<!@(pkg-config --libs-only-L --libs-only-other x11 xi)',