Always use signed leb128 encoding

 According to runs on /system/lib there using
 unsigned leb128 does not save us any additional
 space. In order to keep packing as simple as
 possible switch to using signed leb128 for
 everything.

Bug: http://b/18051137
Change-Id: I1a47cb9eb2175895b3c3f7c13b4c6b1060de86c0
diff --git a/tools/relocation_packer/src/elf_file_unittest.cc b/tools/relocation_packer/src/elf_file_unittest.cc
index 434f101..5271eef 100644
--- a/tools/relocation_packer/src/elf_file_unittest.cc
+++ b/tools/relocation_packer/src/elf_file_unittest.cc
@@ -175,13 +175,19 @@
 
 namespace relocation_packer {
 
-TEST(ElfFile, PackRelocations) {
+TEST(ElfFile, PackRelocationsArm32) {
   RunPackRelocationsTestFor("arm32");
+}
+
+TEST(ElfFile, PackRelocationsArm64) {
   RunPackRelocationsTestFor("arm64");
 }
 
-TEST(ElfFile, UnpackRelocations) {
+TEST(ElfFile, UnpackRelocationsArm32) {
   RunUnpackRelocationsTestFor("arm32");
+}
+
+TEST(ElfFile, UnpackRelocationsArm64) {
   RunUnpackRelocationsTestFor("arm64");
 }