Fixed Xcode 11 atomic-implicit-seq-cst warning with NSString initialization.

	Change on 2019/07/11 by tball <[email protected]>

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=257674734

Author: tomball

jre_emul/Classes/J2ObjC_common.h

@@ -180,7 +180,7 @@ J2OBJC_VOLATILE_ACCESS_DEFN(Double, jdouble)
 #define J2OBJC_STATIC_INIT(CLASS) \
   FOUNDATION_EXPORT _Atomic(jboolean) CLASS##__initialized; \
   __attribute__((always_inline)) inline void CLASS##_initialize() { \
-    if (__builtin_expect(!__c11_atomic_load(&CLASS##__initialized, __ATOMIC_ACQUIRE), 0)) { \
+    if (!__c11_atomic_load(&CLASS##__initialized, __ATOMIC_ACQUIRE)) { \
       [CLASS class]; \
     } \
   }

jre_emul/Classes/NSString+JavaString.h

@@ -326,7 +326,7 @@ FOUNDATION_EXPORT NSString *NSString_java_joinWithJavaLangCharSequence_withJavaL
 // Use the category dummy to initialize static variables for the String class.
 FOUNDATION_EXPORT _Atomic(jboolean) NSString__initialized;
 __attribute__((always_inline)) inline void NSString_initialize() {
-  if (!__builtin_expect(NSString__initialized, true)) {
+  if (!__c11_atomic_load(&NSString__initialized, __ATOMIC_ACQUIRE)) {
     [JreStringCategoryDummy class];
   }
 }