linux: Add "dark-theme" option for BrowserWindow, fixes #352.

atom/browser/native_window_views.cc

@@ -150,6 +150,19 @@ NativeWindowViews::NativeWindowViews(content::WebContents* web_contents,
 
   window_->Init(params);
 
+#if defined(USE_X11)
+  bool use_dark_theme = false;
+  if (options.Get(switches::kDarkTheme, &use_dark_theme) && use_dark_theme) {
+    XDisplay* xdisplay = gfx::GetXDisplay();
+    XChangeProperty(xdisplay, GetAcceleratedWidget(),
+                    XInternAtom(xdisplay, "_GTK_THEME_VARIANT", False),
+                    XInternAtom(xdisplay, "UTF8_STRING", False),
+                    8, PropModeReplace,
+                    reinterpret_cast<const unsigned char*>("dark"),
+                    4);
+  }
+#endif
+
   // Add web view.
   SetLayoutManager(new MenuLayout(kMenuBarHeight));
   set_background(views::Background::CreateStandardPanelBackground());

atom/common/options_switches.cc

@@ -54,6 +54,9 @@ const char kAutoHideMenuBar[] = "auto-hide-menu-bar";
 // Enable window to be resized larger than screen.
 const char kEnableLargerThanScreen[] = "enable-larger-than-screen";
 
+// Forces to use dark theme on Linux.
+const char kDarkTheme[] = "dark-theme";
+
 }  // namespace switches
 
 }  // namespace atom

atom/common/options_switches.h

@@ -34,6 +34,7 @@ extern const char kWebPreferences[];
 extern const char kZoomFactor[];
 extern const char kAutoHideMenuBar[];
 extern const char kEnableLargerThanScreen[];
+extern const char kDarkTheme[];
 
 }  // namespace switches
 

docs/api/browser-window.md

@@ -63,6 +63,8 @@ normal browsers, see [Web Security](web-security.md) for more.
     key is pressed.
   * `enable-larger-than-screen` Boolean - Enable the window to be resized larger
     than screen.
+  * `dark-theme` Boolean - Forces using dark theme for the window, only works on
+    some GTK+3 desktop environments.
   * `web-preferences` Object - Settings of web page's features
     * `javascript` Boolean
     * `web-security` Boolean