[AST] Fix a warning

This patch fixes:

  clang/lib/AST/ASTContext.cpp:931:40: error: field
  'DependentBitIntTypes' will be initialized after field
  'FunctionProtoTypes' [-Werror,-Wreorder-ctor]

Author: kazutakahirata

clang/lib/AST/ASTContext.cpp

@@ -927,12 +927,12 @@ ASTContext::ASTContext(LangOptions &LOpts, SourceManager &SM,
     : ConstantArrayTypes(this_(), ConstantArrayTypesLog2InitSize),
       DependentSizedArrayTypes(this_()), DependentSizedExtVectorTypes(this_()),
       DependentAddressSpaceTypes(this_()), DependentVectorTypes(this_()),
-      DependentSizedMatrixTypes(this_()), DependentTypeOfExprTypes(this_()),
-      DependentDecltypeTypes(this_()), DependentBitIntTypes(this_()),
+      DependentSizedMatrixTypes(this_()),
       FunctionProtoTypes(this_(), FunctionProtoTypesLog2InitSize),
+      DependentTypeOfExprTypes(this_()), DependentDecltypeTypes(this_()),
       TemplateSpecializationTypes(this_()),
       DependentTemplateSpecializationTypes(this_()), AutoTypes(this_()),
-      SubstTemplateTemplateParmPacks(this_()),
+      DependentBitIntTypes(this_()), SubstTemplateTemplateParmPacks(this_()),
       CanonTemplateTemplateParms(this_()), SourceMgr(SM), LangOpts(LOpts),
       NoSanitizeL(new NoSanitizeList(LangOpts.NoSanitizeFiles, SM)),
       XRayFilter(new XRayFunctionFilter(LangOpts.XRayAlwaysInstrumentFiles,