[NFC] Reordering parameters in getFile and getFileOrSTDIN

In future patches I will be setting the IsText parameter frequently so I will refactor the args to be in the following order. I have removed the FileSize parameter because it is never used.

```
  static ErrorOr<std::unique_ptr<MemoryBuffer>>
  getFile(const Twine &Filename, bool IsText = false,
          bool RequiresNullTerminator = true, bool IsVolatile = false);

  static ErrorOr<std::unique_ptr<MemoryBuffer>>
  getFileOrSTDIN(const Twine &Filename, bool IsText = false,
                 bool RequiresNullTerminator = true);

 static ErrorOr<std::unique_ptr<MB>>
 getFileAux(const Twine &Filename, uint64_t MapSize, uint64_t Offset,
            bool IsText, bool RequiresNullTerminator, bool IsVolatile);

  static ErrorOr<std::unique_ptr<WritableMemoryBuffer>>
  getFile(const Twine &Filename, bool IsVolatile = false);
```

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D99182

2 files changed, 6 insertions, 10 deletions

diff --git a/clang/lib/Tooling/JSONCompilationDatabase.cpp b/clang/lib/Tooling/JSONCompilationDatabase.cpp
index 2d8847a..97ba7e4 100644
--- a/clang/lib/Tooling/JSONCompilationDatabase.cpp
+++ b/clang/lib/Tooling/JSONCompilationDatabase.cpp
@@ -198,7 +198,7 @@ JSONCompilationDatabase::loadFromFile(StringRef FilePath,
                                       JSONCommandLineSyntax Syntax) {
   // Don't mmap: if we're a long-lived process, the build system may overwrite.
   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> DatabaseBuffer =
-      llvm::MemoryBuffer::getFile(FilePath, /*FileSize=*/-1,
+      llvm::MemoryBuffer::getFile(FilePath, /*IsText=*/false,
                                   /*RequiresNullTerminator=*/true,
                                   /*IsVolatile=*/true);
   if (std::error_code Result = DatabaseBuffer.getError()) {
diff --git a/clang/tools/arcmt-test/arcmt-test.cpp b/clang/tools/arcmt-test/arcmt-test.cpp
index 778587d..26e123c 100644
--- a/clang/tools/arcmt-test/arcmt-test.cpp
+++ b/clang/tools/arcmt-test/arcmt-test.cpp
@@ -207,15 +207,13 @@ static bool performTransformations(StringRef resourcesPath,
 static bool filesCompareEqual(StringRef fname1, StringRef fname2) {
   using namespace llvm;
 
-  ErrorOr<std::unique_ptr<MemoryBuffer>> file1 = MemoryBuffer::getFile(
-      fname1, /*FileSize=*/-1, /*RequiresNullTerminator=*/true,
-      /*IsVolatile=*/false, /*IsText=*/true);
+  ErrorOr<std::unique_ptr<MemoryBuffer>> file1 =
+      MemoryBuffer::getFile(fname1, /*IsText=*/true);
   if (!file1)
     return false;
 
-  ErrorOr<std::unique_ptr<MemoryBuffer>> file2 = MemoryBuffer::getFile(
-      fname2, /*FileSize=*/-1, /*RequiresNullTerminator=*/true,
-      /*IsVolatile=*/false, /*IsText=*/true);
+  ErrorOr<std::unique_ptr<MemoryBuffer>> file2 =
+      MemoryBuffer::getFile(fname2, /*IsText=*/true);
   if (!file2)
     return false;
 
@@ -244,9 +242,7 @@ static bool verifyTransformedFiles(ArrayRef<std::string> resultFiles) {
   if (RemappingsFile.empty())
     inputBuf = MemoryBuffer::getSTDIN();
   else
-    inputBuf = MemoryBuffer::getFile(RemappingsFile, /*FileSize=*/-1,
-                                     /*RequiresNullTerminator=*/true,
-                                     /*IsVolatile=*/false, /*IsText=*/true);
+    inputBuf = MemoryBuffer::getFile(RemappingsFile, /*IsText=*/true);
   if (!inputBuf) {
     errs() << "error: could not read remappings input\n";
     return true;