Start using new reserved disk GID.

We recently created a new GID that can be granted to critical system
processes, so that the system is usable enough for the user to free
up disk space used by abusive apps.

Define a permission for the GID so we can grant it to system apps,
and add the GID to core apps needed for system stability.  (The list
was mostly derived from filling a disk and seeing what caused the
device to fall over.)

Test: builds, boots
Bug: 62024591
Change-Id: Icdf471ed3bed4eeb8c01f1d39f0b40c1ea098396
diff --git a/packages/Shell/AndroidManifest.xml b/packages/Shell/AndroidManifest.xml
index d675a7a..b3d6357 100644
--- a/packages/Shell/AndroidManifest.xml
+++ b/packages/Shell/AndroidManifest.xml
@@ -43,6 +43,7 @@
     <uses-permission android:name="android.permission.DISABLE_KEYGUARD" />
     <uses-permission android:name="android.permission.MANAGE_NETWORK_POLICY" />
     <uses-permission android:name="android.permission.MANAGE_USB" />
+    <uses-permission android:name="android.permission.USE_RESERVED_DISK" />
     <!-- System tool permissions granted to the shell. -->
     <uses-permission android:name="android.permission.REAL_GET_TASKS" />
     <uses-permission android:name="android.permission.CHANGE_CONFIGURATION" />