chromeos: fix opacity in ash

The client was not always passing in the right translucent value, leading
to the window being marked opaque on the server when it isn't.

BUG=849380
TEST=none

Change-Id: I39f73a9ede381f0310a8532bc76ce700007f1352
Reviewed-on: https://chromium-review.googlesource.com/1103701Reviewed-by: Fady Samuel <fsamuel@chromium.org>
Commit-Queue: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#568149}

ui/views/mus/desktop_window_tree_host_mus.cc

@@ -294,15 +294,10 @@ bool DesktopWindowTreeHostMus::ShouldSendClientAreaToServer() const {
 }
 
 void DesktopWindowTreeHostMus::Init(const Widget::InitParams& params) {
-  // |TYPE_WINDOW| and |TYPE_PANEL| are forced to transparent as otherwise the
-  // window is opaque and the client decorations drawn by the window manager
-  // would not be seen.
-  const bool transparent =
-      params.opacity == Widget::InitParams::TRANSLUCENT_WINDOW ||
-      params.type == Widget::InitParams::TYPE_WINDOW ||
-      params.type == Widget::InitParams::TYPE_PANEL;
-  content_window()->SetTransparent(transparent);
-  window()->SetTransparent(transparent);
+  const bool translucent =
+      MusClient::ShouldMakeWidgetWindowsTranslucent(params);
+  content_window()->SetTransparent(translucent);
+  window()->SetTransparent(translucent);
 
   window()->SetProperty(aura::client::kShowStateKey, params.show_state);
 

ui/views/mus/mus_client.cc

@@ -171,6 +171,16 @@ bool MusClient::ShouldCreateDesktopNativeWidgetAura(
          !init_params.child;
 }
 
+// static
+bool MusClient::ShouldMakeWidgetWindowsTranslucent(
+    const Widget::InitParams& params) {
+  // |TYPE_WINDOW| and |TYPE_PANEL| are forced to translucent so that the
+  // window manager can draw the client decorations.
+  return params.opacity == Widget::InitParams::TRANSLUCENT_WINDOW ||
+         params.type == Widget::InitParams::TYPE_WINDOW ||
+         params.type == Widget::InitParams::TYPE_PANEL;
+}
+
 // static
 std::map<std::string, std::vector<uint8_t>>
 MusClient::ConfigurePropertiesFromParams(
@@ -189,8 +199,8 @@ MusClient::ConfigurePropertiesFromParams(
       mojo::ConvertTo<TransportType>(init_params.CanActivate());
 
   properties[WindowManager::kTranslucent_InitProperty] =
-      mojo::ConvertTo<TransportType>(init_params.opacity ==
-                                     Widget::InitParams::TRANSLUCENT_WINDOW);
+      mojo::ConvertTo<TransportType>(
+          ShouldMakeWidgetWindowsTranslucent(init_params));
 
   if (!init_params.bounds.IsEmpty()) {
     properties[WindowManager::kBounds_InitProperty] =

ui/views/mus/mus_client.h

@@ -103,6 +103,10 @@ class VIEWS_MUS_EXPORT MusClient : public aura::WindowTreeClientDelegate,
   static bool ShouldCreateDesktopNativeWidgetAura(
       const Widget::InitParams& init_params);
 
+  // Returns true if the windows backing the Widget should be made translucent.
+  static bool ShouldMakeWidgetWindowsTranslucent(
+      const Widget::InitParams& params);
+
   // Returns the properties to supply to mus when creating a window.
   static std::map<std::string, std::vector<uint8_t>>
   ConfigurePropertiesFromParams(const Widget::InitParams& init_params);