[llvm][TextAPI] add Default FileType value to InterfaceFile Objects

* This silences msan errors

(cherry picked from commit e61e761)

Author: cyndyishida

llvm/include/llvm/TextAPI/InterfaceFile.h

@@ -442,7 +442,7 @@ class InterfaceFile {
 
   TargetList Targets;
   std::string Path;
-  FileType FileKind;
+  FileType FileKind{FileType::Invalid};
   std::string InstallName;
   PackedVersion CurrentVersion;
   PackedVersion CompatibilityVersion;

llvm/unittests/TextAPI/TextStubV3Tests.cpp

@@ -940,6 +940,7 @@ TEST(TBDv3, InterfaceInequality) {
   }));
   EXPECT_TRUE(checkEqualityOnTransform(FileA, FileB, [](InterfaceFile *File) {
     InterfaceFile Document;
+    Document.setFileType(FileType::TBD_V3);
     Document.addTargets(TargetList{Target(AK_armv7, PLATFORM_IOS),
                                    Target(AK_arm64, PLATFORM_IOS)});
     Document.setInstallName("/System/Library/Frameworks/A.framework/A");

llvm/unittests/TextAPI/TextStubV4Tests.cpp

@@ -1176,6 +1176,7 @@ TEST(TBDv4, InterfaceInequality) {
   }));
   EXPECT_TRUE(checkEqualityOnTransform(FileA, FileB, [](InterfaceFile *File) {
     InterfaceFile Document;
+    Document.setFileType(FileType::TBD_V4);
     Document.addTargets(TargetList{Target(AK_i386, PLATFORM_MACOS),
                                    Target(AK_x86_64, PLATFORM_MACOS)});
     Document.setInstallName("/System/Library/Frameworks/A.framework/A");