SystemUI: unregister ContentObserver

We were leaking memory.

Change-Id: Id40e7dd78c879a6b7fa4ff7584e47a6005dfefda
PS2: move instanciating to the SearchPanelView constructor
PS3: more possible memory leaks
Remove the fixed-length buffer in DdmHandleNativeHeap.getLeakInfo.

It was possible to overrun this buffer, and even if you did fill
the buffer in a single read and exit the loop, the "string" still
wouldn't be terminated.

Bug: 8468088
Change-Id: Ia19f4d26dfd79e7b63807a7ec9540b932163d246
services: don't clear wallpaper when SystemUI
disconnects.

When we restart SystemUI (or the user), sometimes
the wallpaper would get cleared. This patch just
captures its originating component and
if that is our SystemUI component, ignore the event.

Change-Id: I3e159dc2c013e7d7e552e3c0cef55e3ab970ca87
Signed-off-by: Roman Birg <romanbirg@gmail.com>