Fix status icons not showing up for xfce4-indicator-plugin

R=thestig

Change-Id: I3a4d25202b81ab92f4ef551bb5f32595d88d4f4b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1934779
Auto-Submit: Thomas Anderson <thomasanderson@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/master@{#720793}

chrome/browser/ui/views/status_icons/status_icon_linux_x11.cc

@@ -39,6 +39,14 @@ constexpr int kXembedInfoFlags = kXembedFlagMap;
 
 const int16_t kInitialWindowPos = std::numeric_limits<int16_t>::min();
 
+class StatusIconWidget : public views::Widget {
+ public:
+  // xfce4-indicator-plugin requires a min size hint to be set on the window
+  // (and it must be at least 2x2), otherwise it will not allocate any space to
+  // the status icon window.
+  gfx::Size GetMinimumSize() const override { return gfx::Size(2, 2); }
+};
+
 }  // namespace
 
 StatusIconLinuxX11::StatusIconLinuxX11() : Button(this) {}
@@ -68,7 +76,7 @@ void StatusIconLinuxX11::OnSetDelegate() {
     return;
   }
 
-  widget_ = std::make_unique<views::Widget>();
+  widget_ = std::make_unique<StatusIconWidget>();
 
   auto native_widget =
       std::make_unique<views::DesktopNativeWidgetAura>(widget_.get());