Change pResolveString entrypoint to kSaveEverything.

Test: Run ART test suite including gcstress on host and Nexus 9.
Test: Run ART test suite including gcstress with baker CC on host and Nexus 9.
Bug: 20323084
Change-Id: I63c21a7d3be8ff7a5765b5003c85b5317635efe6
diff --git a/runtime/entrypoints/quick/quick_dexcache_entrypoints.cc b/runtime/entrypoints/quick/quick_dexcache_entrypoints.cc
index 4311d19..2a3ffab 100644
--- a/runtime/entrypoints/quick/quick_dexcache_entrypoints.cc
+++ b/runtime/entrypoints/quick/quick_dexcache_entrypoints.cc
@@ -60,7 +60,11 @@
 extern "C" mirror::String* artResolveStringFromCode(int32_t string_idx, Thread* self)
     REQUIRES_SHARED(Locks::mutator_lock_) {
   ScopedQuickEntrypointChecks sqec(self);
-  auto* caller = GetCalleeSaveMethodCaller(self, Runtime::kSaveRefsOnly);
+  auto* caller = GetCalleeSaveMethodCaller(
+      self,
+      // TODO: Change art_quick_resolve_string on MIPS and MIPS64 to kSaveEverything.
+      (kRuntimeISA == kMips || kRuntimeISA == kMips64) ? Runtime::kSaveRefsOnly
+                                                       : Runtime::kSaveEverything);
   mirror::String* result = ResolveStringFromCode(caller, string_idx);
   if (LIKELY(result != nullptr)) {
     // For AOT code, we need a write barrier for the dex cache that holds the GC roots in the .bss.