[WIP] Multi-window

This is a big work in progress, which currently has some bugs,
but begins to look okay.

You can already multitask a little bit, by using the
app switcher and long-pressing an icon, then select "Add to
Split View".
Last window touched gets the key focus.

Code is very ugly, I know. Don't merge it, don't use it
for now. Unless you want to make your code ugly.

Enjoy :)

PS 11-18: Rebase

Change-Id: I4a03a84539fd3ac1273f0d3503fe8fafcd16be26

Conflicts:
	packages/SystemUI/res/values/custom_strings.xml
Squashed FML changes.

Fix aliasing violation.

frameworks/base: Fix build in ISO C++11 mode

Fix various incompatibilities with ISO C++11:
- Assumption that char16_t is defined to uint16_t
- constexpr usage
- macro constructs that could be interpreted as string literals
- enum typesafety

Signed-off-by: Amit Pundir <amit.pundir@linaro.org>

Conflicts:
	core/jni/android_os_FileUtils.cpp

base: Fix build after Parcel ABI fix in Binder

Adapt code to the fact that writeString16's first parameter
is now an uint16_t* to match the old ABI

Change-Id: I138af645c877f343f0490152b9702698b7d36582
Signed-off-by: Bernhard Rosenkraenzer <Bernhard.Rosenkranzer@linaro.org>

frameworks/base: Fix compile errors

Fix ISO C++11 incompatibility in TextLayoutCache and
aliasing violation in FontRenderer

Signed-off-by: Amit Pundir <amit.pundir@linaro.org>

frameworks/base: Fix build in ISO C++11 mode

Change-Id: I5d3ba44cc9faa5826a5a0a6b37c8f0eb2872e1ac
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>

hwui: Fix build in ISO C++11 mode

Make sure log calls can't be confused with C++11 string literals

Change-Id: I1d458e92e690f6f2b922a05494db8c01da54e460
Signed-off-by: Bernhard Rosenkraenzer <Bernhard.Rosenkranzer@linaro.org>

More C++11 fixings.

More C++11 fixes. More.

Fix confusion about whether or not output() should be const

It probably should be const, but it isn't on master - let's try to
be closer to next upstream

Change-Id: Id26bf19d94a36d83b57488e8bd8d86fa21e784b2
Signed-off-by: Bernhard Rosenkränzer <Bernhard.Rosenkranzer@linaro.org>
core/jni: Disable strict aliasing unless told otherwise for now.

I just want this stuff to compile now at this point.

Looking at this with a fresh perspective later is probably for the best.