Add a factory and defines for native Linux surfaces.

ui/gl/gl.gyp

Index: ui/gl/gl.gyp
diff --git a/ui/gl/gl.gyp b/ui/gl/gl.gyp
index 3f2b35586cd81322bc1768f33dfab76ec362e0dc..2f8a053d41a8d3a61e16a405ea1a6de2562429e8 100644
--- a/ui/gl/gl.gyp
+++ b/ui/gl/gl.gyp
@@ -67,6 +67,7 @@
         'gl_context.h',
         'gl_context_android.cc',
         'gl_context_mac.mm',
+        'gl_context_nsl.cc',
         'gl_context_osmesa.cc',
         'gl_context_osmesa.h',
         'gl_context_stub.cc',
@@ -82,6 +83,7 @@
         'gl_image.h',
         'gl_image_android.cc',
         'gl_image_mac.cc',
+        'gl_image_nsl.cc',
         'gl_image_stub.cc',
         'gl_image_stub.h',
         'gl_image_win.cc',
@@ -90,6 +92,7 @@
         'gl_implementation.h',
         'gl_implementation_android.cc',
         'gl_implementation_mac.cc',
+        'gl_implementation_nsl.cc',
         'gl_implementation_win.cc',
         'gl_implementation_x11.cc',
         'gl_interface.cc',
@@ -104,6 +107,7 @@
         'gl_surface.h',
         'gl_surface_android.cc',
         'gl_surface_mac.cc',
+        'gl_surface_nsl.cc',
         'gl_surface_stub.cc',
         'gl_surface_stub.h',
         'gl_surface_win.cc',
@@ -129,6 +133,24 @@
         '<(gl_binding_output_dir)/gl_bindings_autogen_osmesa.h',
         '<(gl_binding_output_dir)/gl_interface_autogen_gl.h',
       ],
+      'target_conditions': [
+        ['<(use_native_surface_linux) == 1', {
+          'sources!': [
+            'gl_context_linux.cc',
+            'gl_image_linux.cc',
+            'gl_implementation_linux.cc',
+            'gl_surface_linux.cc',
+          ],
+        },
+        { # use_native_surface_linux == 0
+          'sources!': [
+            'gl_context_nsl.cc',
+            'gl_implementation_nsl.cc',
+            'gl_surface_nsl.cc',
+            'gl_image_nsl.cc',
+        ],
+        }],
+      ],
       # hard_dependency is necessary for this target because it has actions
       # that generate header files included by dependent targets. The header
       # files must be generated before the dependents are compiled. The usual
@@ -188,7 +210,7 @@
         },
       ],
       'conditions': [
-        ['OS in ("win", "android") or (OS == "linux" and use_x11 == 1)', {
+        ['OS in ("win", "android") or (OS == "linux" and (use_x11 == 1 or use_native_surface_linux == 1))', {
           'sources': [
             'async_pixel_transfer_delegate_egl.cc',
             'async_pixel_transfer_delegate_egl.h',