arc: Set custom icon in shelf for ARC apps.

components/arc/common/app.mojom

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
-// Next MinVersion: 19
+// Next MinVersion: 20
 
 module arc.mojom;
 
 import "scale_factor.mojom";
 import "screen_rect.mojom";
 
 // Describes OrientationLock request.
 // Note: ChromeOS currently assumes the internal panel is always landscape.
 // All rotation angles mentioned here are measured clockwise.
 [Extensible]
@@ skipping 52 matching lines @@
 // Page for ShowPackageInfoOnPage.
 [Extensible]
 enum ShowPackageInfoPage {
   // The main package info page.
   MAIN = 0,
 
   // Page for managing links assigned to the app.
   MANAGE_LINKS = 1,
 };
 
-// Next method ID: 17
+// Next method ID: 18
 interface AppHost {
   // Sends newly added ARC app to Chrome. This message is sent when ARC receives
   // package added notification. Multiple apps may be added in the one package.
   [MinVersion=1] OnAppAddedDeprecated@2(AppInfo app);
 
   // Receives an icon of required |scale_factor| for specific ARC app. The app
   // is defined by |package_name| and |activity|. The icon content cannot be
   // empty and must match to |scale_factor| assuming 48x48 for
   // SCALE_FACTOR_100P.  |scale_factor| is an enum defined at ui/base/layout.h.
   // |icon_png_data| is a png-encoded image.
@@ skipping 32 matching lines @@
                                  string activity@2,
                                  [MinVersion=13] string? name@3,
                                  [MinVersion=15] string? intent@4);
 
   // Notifies that task has been destroyed.
   [MinVersion=4] OnTaskDestroyed@5(int32 task_id);
 
   // Notifies that task has been activated.
   [MinVersion=4] OnTaskSetActive@6(int32 task_id);
 
+  // Sends task description.
+  [MinVersion=19] OnTaskSetDescription@17(int32 task_id,
+                                          string label,
+                                          array<uint8> icon_png_data);

[reveman, 2017/05/18 16:46:03]

Sending malicious image data to chrome is a well known attack vector. This is
why we do all image decoding in sandboxed renderer processes for the web. How
are we protecting against these type of attacks in this case? Can apps control
the png data sent to Chrome? That a compromised Android container can use this
is bad enough and if apps can control this then I think that's really bad.

Please get a security review before you land this change.

[khmel, 2017/05/18 17:29:35]

We have several places already in this mojo to send icon data, for app and for
shortcuts. Png data is compressed by ArcAppLauncherService from bitmap, the same
as for app and shorcuts. Any icon sent via this mojo interface is processed via
ImageDecoder::Start which is "sandboxed" for security reason. So this call does
not add any new to security. Anyway mojo files are reviewed by special persons.

+
   // Notifies that notifications enabled settings in Android is changed.
   [MinVersion=7] OnNotificationsEnabledChanged@7(string package_name,
                                                  bool enabled);
 
   // Notifies that an application shortcut needs to be created.
   [MinVersion=9] OnInstallShortcut@11(ShortcutInfo shortcut);
 
   // Notifies that Play Store installation has been started. |package_name|
   // specifies installation package
   [MinVersion=16] OnInstallationStarted@14(
@@ skipping 81 matching lines @@
                                            ShowPackageInfoPage page,
                                            ScreenRect dimension_on_screen);
 
   // Sets notification setting for the package.
   [MinVersion=6] SetNotificationsEnabled@10(string package_name, bool enabled);
 
   // Sends a request to ARC to uninstall the given package.  Error (if ever
   // happens) is ignored, and uninstall option should appear in the UI.
   [MinVersion=2] UninstallPackage@5(string package_name);
 };