Remove CFX_BufferSeekableReadStream.

Replace it with CFX_ReadOnlyMemoryStream, which does the same thing.
Take some checks from CFX_BufferSeekableReadStream and add them
CFX_ReadOnlyMemoryStream.

Change-Id: I25554c3aec3ec96967f8df16ca68a64dba121b6f
Reviewed-on: https://pdfium-review.googlesource.com/40070
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/core/fxcrt/cfx_readonlymemorystream.cpp b/core/fxcrt/cfx_readonlymemorystream.cpp
index a01ed2e474..0a1a53a456 100644
--- a/core/fxcrt/cfx_readonlymemorystream.cpp
+++ b/core/fxcrt/cfx_readonlymemorystream.cpp
@@ -21,7 +21,7 @@ FX_FILESIZE CFX_ReadOnlyMemoryStream::GetSize() {
 bool CFX_ReadOnlyMemoryStream::ReadBlock(void* buffer,
                                          FX_FILESIZE offset,
                                          size_t size) {
-  if (offset < 0)
+  if (!buffer || offset < 0 || size == 0)
     return false;
 
   FX_SAFE_SIZE_T pos = size;