Enable debugging of RS code under GDB

- Add/integrate GDBJITRegistrar support class for interfacing with GDB
-- Once the GDBJITRegistrar is merged into LLVM trunk (and AOSP upgrades LLVM)
   all files GDB* should be removed, and replaced with appropriate includes

- Basic [host|target]-side integration tests
-- host-tests: use bcc driver and clang to verify gdb output
-- target-tests: run skeleton apk on target and verify gdb output

- Add support for optimization_level metadata in bcinfo, libbcc
-- Disabled some LTO passes when optimization_level = 0
-- move register allocator registration after metadata inspection

- Initial version of android-commands.py GDB plugin (for test infrastructure)
-- relevant commands: load-android-app, run-android-app, start-android-app
-- tested versions: gdb (7.2, 7.3), python (2.6, 2.7)

- build 'bcc' driver tool by default in eng builds

Change-Id: I99e0c11c8591c6d911632c1dcc82dd8fbe1244a8
diff --git a/lib/ExecutionEngine/Compiler.h b/lib/ExecutionEngine/Compiler.h
index 6030e40..4063edb 100644
--- a/lib/ExecutionEngine/Compiler.h
+++ b/lib/ExecutionEngine/Compiler.h
@@ -177,7 +177,8 @@
 
     int runLTO(llvm::TargetData *TD,
                llvm::NamedMDNode const *ExportVarMetadata,
-               llvm::NamedMDNode const *ExportFuncMetadata);
+               llvm::NamedMDNode const *ExportFuncMetadata,
+               llvm::CodeGenOpt::Level OptimizationLevel);
 
     bool hasError() const {
       return !mError.empty();