in the attempt to fix 627393, changed IFX_FileRead's readBlock to return the length it reads

core/fxcrt/extension.h

Index: core/fxcrt/extension.h
diff --git a/core/fxcrt/extension.h b/core/fxcrt/extension.h
index d4fd0931f4ebb60d14ed9bbf21acef2d4fc7c88b..42b7bc456351186998f1e52b48090d27e981a5d8 100644
--- a/core/fxcrt/extension.h
+++ b/core/fxcrt/extension.h
@@ -65,7 +65,7 @@ class CFX_CRTFileStream final : public IFX_FileStream {
   FX_FILESIZE GetSize() override;
   FX_BOOL IsEOF() override;
   FX_FILESIZE GetPosition() override;
-  FX_BOOL ReadBlock(void* buffer, FX_FILESIZE offset, size_t size) override;
+  size_t ReadBlock(void* buffer, FX_FILESIZE offset, size_t size) override;
   size_t ReadBlock(void* buffer, size_t size) override;
   FX_BOOL WriteBlock(const void* buffer,
                      FX_FILESIZE offset,
@@ -92,7 +92,7 @@ class CFX_MemoryStream final : public IFX_MemoryStream {
   FX_FILESIZE GetSize() override;
   FX_BOOL IsEOF() override;
   FX_FILESIZE GetPosition() override;
-  FX_BOOL ReadBlock(void* buffer, FX_FILESIZE offset, size_t size) override;
+  size_t ReadBlock(void* buffer, FX_FILESIZE offset, size_t size) override;
   size_t ReadBlock(void* buffer, size_t size) override;
   FX_BOOL WriteBlock(const void* buffer,
                      FX_FILESIZE offset,