[PATCH] Introduce new gold plugin option "relocation-pic"

[Alexey Volkov]

On Android user doesn't have to pass -fPIC or -fPIE option.
Clang is turning on PIC mode (not PIE) without any user input when targeting to Android.
However when producing executable compiler has no special options (-pie) for linker.
So linker produces executable from PIC objects without -pie option.
So final executable is not pure PIE, it's executable formed from PIC code.
This is what we have now on Android.
Adding -pie option to linker could change produced code which could be surprising to user.
Since -pie needed only to fix or workaround this bug I propose to have -pie only with LTO enabled.

http://reviews.llvm.org/D2668