sensorservice: Add legacy sensors fusion.

This change allows devices with accelerometer & magnetometer but
without gyroscope to still get virtual sensors such as Gravity,
Linear Acceleration and Rotation Vector.

Change-Id: Ibb90b70845c766ab52c843557446e34649a7d6d9
Merge "sensorservice: Add legacy sensors fusion." into cm-10.1
build/phone-xhdpi-1024-dalvik-heap.mk Revert AOSP heapgrowthlimit change from 64 to 96

This reverts part of AOSP change at

https://android.googlesource.com/platform/frameworks/native/+/c84e9844d621223d14178be521

Possible performance issues have arisen because of it. Discussion at

http://code.google.com/p/android/issues/detail?id=40961

Patch Set 2: Clean up commit message

Change-Id: Id7e3324607f92553a98e4d47da58a322e4fba657
Merge branch 'cm-10.1' of git://github.com/CyanogenMod/android_frameworks_native into HEAD