[mus+ash] Fixes minimum browser window size (store / retrieve kPreferredSize property)

services/ui/public/interfaces/window_manager.mojom

Index: services/ui/public/interfaces/window_manager.mojom
diff --git a/services/ui/public/interfaces/window_manager.mojom b/services/ui/public/interfaces/window_manager.mojom
index 3ddbe2ce6567a53792741d58db14e6e18729dd78..636ba0cfd97a7759e673773484d84e96cc901c7f 100644
--- a/services/ui/public/interfaces/window_manager.mojom
+++ b/services/ui/public/interfaces/window_manager.mojom
@@ -102,6 +102,10 @@ interface WindowManager {
   // Type: bool.
   const string kImmersiveFullscreen_Property = "prop:immersive-fullscreen";
 
+  // The window's minimum size as defined by its content. Maps to
+  // aura::client::kMinimumSize_Property. Type: gfx::Size.
+  const string kMinimumSize_Property = "prop:minimum-size";
+
   // Internal window name. Useful for debugging. Maps to aura::client::kNameKey.
   // Type: mojom::String
   const string kName_Property = "prop:name";