Added missing permission declaration on <service> tag of AccessibilityService guide documentation (Building Accessibility Services)

With code snippet on current docs, the accessibility service does not show up on the Settings > Accessibility > Services list, with API level 17 or higher. In order to declare service correctly, user have to declare "permission" property with value of "android.permission.BIND_ACCESSIBILITY_SERVICE".

Change-Id: I70c8f98d4ff6fd2286bf5866098b22443afb6cd9
Wrong argument: handleUnstableProviderDiedLocked

mProvider is HashMap<ProviderKey, ProviderClientRecord>. String
is not correct object for KEY. Complete removal using iterator.

Change-Id: I51e4576544ef02ede6f96938689dd4e43ec6eb4f
Merge https://github.com/PSX-PureSpeed/android_frameworks_base into HEAD