[DO NOT MERGE]build: fix renderscript header inclusion

- to build frameworks/rs with the prebuilt clang

credits to @xboxfanj for the idea

Change-Id: Ifb79d60840bdd8e8dbf5a50cf73b4ae4082e4c3a
Signed-off-by: bart452 <bart4524@gmail.com>
releasetools: Properly handle custom values for tools

Rather than writing these values to their own files, store them
in the target_files META/misc_info.txt. This way, we don't need to
download and parse through multiple files when using signing/release
tools.

Change-Id: I6f845fc055e4ef2ed4adf9628cca505e99b2a9fa
build: restore order to the universe... or at least non-clang renderscript includes

Change-Id: Ie6a4a0fd5c207ef55ac1797efa806d56d050fe68