Revert "Revert "Store resolved Strings for AOT code in .bss.""

Fixed oat_test to keep dex files alive. Fixed mips build.
Rewritten the .bss GC root visiting and added write barrier
to the artResolveStringFromCode().

Test: build aosp_mips-eng
Test: m ART_DEFAULT_GC_TYPE=SS test-art-target-host-gtest-oat_test
Test: Run ART test suite on host and Nexus 9.
Bug: 20323084
Bug: 30627598

This reverts commit 5f926055cb88089d8ca27243f35a9dfd89d981f0.

Change-Id: I07fa2278d82b8eb64964c9a4b66cb93726ccda6b
diff --git a/compiler/optimizing/code_generator_arm.h b/compiler/optimizing/code_generator_arm.h
index 6416d40..ef2e23f 100644
--- a/compiler/optimizing/code_generator_arm.h
+++ b/compiler/optimizing/code_generator_arm.h
@@ -593,6 +593,10 @@
                                           uint32_t offset_or_index,
                                           ArenaDeque<PcRelativePatchInfo>* patches);
 
+  template <LinkerPatch (*Factory)(size_t, const DexFile*, uint32_t, uint32_t)>
+  static void EmitPcRelativeLinkerPatches(const ArenaDeque<PcRelativePatchInfo>& infos,
+                                          ArenaVector<LinkerPatch>* linker_patches);
+
   // Labels for each block that will be compiled.
   Label* block_labels_;  // Indexed by block id.
   Label frame_entry_label_;
@@ -609,12 +613,12 @@
   MethodToLiteralMap call_patches_;
   // Relative call patch info.
   // Using ArenaDeque<> which retains element addresses on push/emplace_back().
-  ArenaDeque<MethodPatchInfo<Label>> relative_call_patches_;
+  ArenaDeque<PatchInfo<Label>> relative_call_patches_;
   // PC-relative patch info for each HArmDexCacheArraysBase.
   ArenaDeque<PcRelativePatchInfo> pc_relative_dex_cache_patches_;
   // Deduplication map for boot string literals for kBootImageLinkTimeAddress.
   BootStringToLiteralMap boot_image_string_patches_;
-  // PC-relative String patch info.
+  // PC-relative String patch info; type depends on configuration (app .bss or boot image PIC).
   ArenaDeque<PcRelativePatchInfo> pc_relative_string_patches_;
   // Deduplication map for boot type literals for kBootImageLinkTimeAddress.
   BootTypeToLiteralMap boot_image_type_patches_;