X11: Use better visuals for OpenGL

ui/gl/gl_surface_glx.cc

Index: ui/gl/gl_surface_glx.cc
diff --git a/ui/gl/gl_surface_glx.cc b/ui/gl/gl_surface_glx.cc
index add3a62fc587b0447fb9a2d8ef4e51e0e728d1d9..191da0804469399e1baf580e1f72e4be2b876b42 100644
--- a/ui/gl/gl_surface_glx.cc
+++ b/ui/gl/gl_surface_glx.cc
@@ -29,6 +29,7 @@ extern "C" {
 #include "ui/gfx/x/x11_types.h"
 #include "ui/gl/gl_bindings.h"
 #include "ui/gl/gl_implementation.h"
+#include "ui/gl/gl_visual_picker_glx.h"
 #include "ui/gl/sync_control_vsync_provider.h"
 
 namespace gl {
@@ -50,6 +51,11 @@ bool g_glx_get_msc_rate_oml_supported = false;
 
 bool g_glx_sgi_video_sync_supported = false;
 
+// A 24-bit RGB visual and colormap to use when creating offscreen surfaces.
+Visual* g_visual = nullptr;
+int g_depth = CopyFromParent;
+Colormap g_colormap = CopyFromParent;
+
 GLXFBConfig GetConfigForWindow(Display* display,
                                gfx::AcceleratedWidget window) {
   DCHECK(window != 0);
@@ -109,9 +115,6 @@ bool CreateDummyWindow(Display* display) {
   DCHECK(display);
   gfx::AcceleratedWidget parent_window =
       RootWindow(display, DefaultScreen(display));
-  // We create a window with CopyFromParent visual so that we have the same
-  // visual as NativeViewGLSurfaceGLX (i.e. same GLXFBConfig), to ensure
-  // contexts are compatible and can be made current with either.
   gfx::AcceleratedWidget window =
       XCreateWindow(display, parent_window, 0, 0, 1, 1, 0, CopyFromParent,
                     InputOutput, CopyFromParent, 0, nullptr);
@@ -422,6 +425,13 @@ bool GLSurfaceGLX::InitializeOneOff() {
   g_glx_get_msc_rate_oml_supported = g_glx_oml_sync_control_supported;
   g_glx_sgi_video_sync_supported = HasGLXExtension("GLX_SGI_video_sync");
 
+  const XVisualInfo& visual_info =
+      gl::GLVisualPickerGLX::GetInstance()->system_visual();
+  g_visual = visual_info.visual;
+  g_depth = visual_info.depth;
+  g_colormap = XCreateColormap(g_display, DefaultRootWindow(g_display),
+                               visual_info.visual, AllocNone);
+
   // We create a dummy unmapped window for both the main Display and the video
   // sync Display so that the Nvidia driver can initialize itself before the
   // sandbox is set up.
@@ -507,6 +517,7 @@ bool NativeViewGLSurfaceGLX::Initialize(GLSurface::Format format) {
     return false;
   }
   size_ = gfx::Size(attributes.width, attributes.height);
+  visual_id_ = XVisualIDFromVisual(attributes.visual);
   // Create a child window, with a CopyFromParent visual (to avoid inducing
   // extra blits in the driver), that we can resize exactly in Resize(),
   // correctly ordered with GL, so that we don't have invalid transient states.
@@ -641,15 +652,14 @@ UnmappedNativeViewGLSurfaceGLX::UnmappedNativeViewGLSurfaceGLX(
 bool UnmappedNativeViewGLSurfaceGLX::Initialize(GLSurface::Format format) {
   DCHECK(!window_);
 
-  gfx::AcceleratedWidget parent_window =
-      RootWindow(g_display, DefaultScreen(g_display));
+  gfx::AcceleratedWidget parent_window = DefaultRootWindow(g_display);
 
-  // We create a window with CopyFromParent visual so that we have the same
-  // visual as NativeViewGLSurfaceGLX (i.e. same GLXFBConfig), to ensure
-  // contexts are compatible and can be made current with either.
+  XSetWindowAttributes attrs;
+  attrs.border_pixel = 0;
+  attrs.colormap = g_colormap;
   window_ = XCreateWindow(g_display, parent_window, 0, 0, size_.width(),
-                          size_.height(), 0, CopyFromParent, InputOutput,
-                          CopyFromParent, 0, nullptr);
+                          size_.height(), 0, g_depth, InputOutput, g_visual,
+                          CWBorderPixel | CWColormap, &attrs);
   GetConfig();
   DCHECK(config_);
   glx_window_ = glXCreateWindow(g_display, config_, window_, NULL);