settings: properly count preferences in group

When the first preference in a settings preference fragment is a caterory, this method cannot
find the first preference of the group, returning an incorrect position.
xe: Lockscreen Settings -> Screen settings

Reason for that is that there's no way to differentiate 0 from -0. Fix
that by avoiding overloading integer semantics and clearly splitting the
result count from the 'was stopAt found' flag.

Change-Id: I68cfde27b9860246b1cc3671dfb35320c4ff3ea8
settings: prevent multiple highlights in settings search

xe: Developer Options -> Launch Tools. The Process Stats is highlighted along
with Launch Tools, because the view of the latter is reused for the former and the
latter later gets a new view. Fix that by making sure to cancel old
highlights when triggering a new one.

Change-Id: Ibf2068628e5024d61495d4f9968811c77e120918
Signed-off-by: Jorge Ruesga <jorge@ruesga.com>
Apply match spans synchronously to avoid a race condition

Using the match start/end positions from both the main thread (when
updating UI) and the filter thread (when the filter constraint changed)
at the same time can lead into exceptions. Make sure to update the positions used by
the UI thread only from there.

07-11 03:26:18.845: E/AndroidRuntime(12765): Process: com.android.settings, PID: 12765
07-11 03:26:18.845: E/AndroidRuntime(12765): java.lang.IndexOutOfBoundsException: setSpan (-1 ... -1) starts before 0
07-11 03:26:18.845: E/AndroidRuntime(12765): at android.text.SpannableStringBuilder.checkRange(SpannableStringBuilder.java:1021)
07-11 03:26:18.845: E/AndroidRuntime(12765): at android.text.SpannableStringBuilder.setSpan(SpannableStringBuilder.java:592)
07-11 03:26:18.845: E/AndroidRuntime(12765): at android.text.SpannableStringBuilder.setSpan(SpannableStringBuilder.java:588)
07-11 03:26:18.845: E/AndroidRuntime(12765): at com.android.settings.search.SettingsSearchFilterAdapter.getView(SettingsSearchFilterAdapter.java:216)
07-11 03:26:18.845: E/AndroidRuntime(12765): at android.widget.AbsListView.obtainView(AbsListView.java:2255)
07-11 03:26:18.845: E/AndroidRuntime(12765): at android.widget.ListPopupWindow.obtainView(ListPopupWindow.java:1585)
07-11 03:26:18.845: E/AndroidRuntime(12765): at android.widget.ListView.measureHeightOfChildren(ListView.java:1263)
07-11 03:26:18.845: E/AndroidRuntime(12765): at android.widget.ListPopupWindow.buildDropDown(ListPopupWindow.java:1167)
07-11 03:26:18.845: E/AndroidRuntime(12765): at android.widget.ListPopupWindow.show(ListPopupWindow.java:554)
07-11 03:26:18.845: E/AndroidRuntime(12765): at android.widget.AutoCompleteTextView.showDropDown(AutoCompleteTextView.java:1096)
07-11 03:26:18.845: E/AndroidRuntime(12765): at android.widget.AutoCompleteTextView.updateDropDownForFilter(AutoCompleteTextView.java:971)
07-11 03:26:18.845: E/AndroidRuntime(12765): at android.widget.AutoCompleteTextView.access00(AutoCompleteTextView.java:91)
07-11 03:26:18.845: E/AndroidRuntime(12765): at android.widget.AutoCompleteTextView.run(AutoCompleteTextView.java:1268)
07-11 03:26:18.845: E/AndroidRuntime(12765): at android.os.Handler.handleCallback(Handler.java:733)
07-11 03:26:18.845: E/AndroidRuntime(12765): at android.os.Handler.dispatchMessage(Handler.java:95)
07-11 03:26:18.845: E/AndroidRuntime(12765): at android.os.Looper.loop(Looper.java:136)
07-11 03:26:18.845: E/AndroidRuntime(12765): at android.app.ActivityThread.main(ActivityThread.java:5140)
07-11 03:26:18.845: E/AndroidRuntime(12765): at java.lang.reflect.Method.invokeNative(Native Method)
07-11 03:26:18.845: E/AndroidRuntime(12765): at java.lang.reflect.Method.invoke(Method.java:515)
07-11 03:26:18.845: E/AndroidRuntime(12765): at com.android.internal.os.ZygoteInit.run(ZygoteInit.java:795)
07-11 03:26:18.845: E/AndroidRuntime(12765): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:611)
07-11 03:26:18.845: E/AndroidRuntime(12765): at dalvik.system.NativeStart.main(Native Method)

Change-Id: I60cff301d3bfb15ea2bbf63fcae524af0ae0b8a6
Settings: Always show search on multipane devices.

    - Disable in more fragments for clean up.

Change-Id: Ia82f89ca8394e9d3dcf7dc80d2dfccdbe6fa9bc7