Issue Description:

The following reflection tests fail when run against an Android target:

• test/Reflection/box_descriptors.sil

• test/Reflection/capture_descriptors.sil

• test/Reflection/typeref_decoding.swift

• test/Reflection/typeref_decoding_imported.swift

• test/Reflection/typeref_lowering.swift

All of them use swift-reflection-dump, and all of them fail with the following message:

/usr/bin/ld.gold: fatal error: -shared and -pie are incompatible
clang-3.9: error: linker command failed with exit code 1 (use -v to see invocation)
<unknown>:0: error: link command failed with exit code 1 (use -v to see invocation)

I think these tests pass on Linux targets that use the gold linker. Perhaps we need to modify the %target-swift-reflection-dump substitution on Android?

Prerequisites:

• An Ubuntu 15.10 development environment capable of building Swift from source.

• A physical Android device.

Helpful skills:
Familiarity with Python and llvm-lit would be helpful, but not strictly necessary.

Starting point:

1. Follow the instructions in docs/Android.md to build and run the test suite on a physical Android device. Confirm this test still fails.

2. Take a look at the %target-swift-reflection-dump substitution on Android:

   swift/test/lit.cfg

   Lines 952 to 953 in add621a

   	config.substitutions.append(('%target-swift-reflection-test', lit.util.which('swift-reflection-test{variant_suffix}'.format(variant_suffix=config.variant_suffix), config.environment['PATH'])))
   	config.substitutions.append(('%target-swift-reflection-dump', '{} {} {}'.format(config.swift_reflection_dump, '-arch', run_cpu)))

   – maybe these need to be changed for Android? Or perhaps some other substitution in that file is passing bad linker flags?