Fix -Wnon-virtual-dtor compiler warnings.

This is done by explicitly adding a virtual dtor to interface classes,
since the cost is small given that there are already virtual functions.

The exceptions are for classes that have a Release() or Delete() method,
in which case it is non-virtual and protected to indicate that the virtual
class is never the deletion point.

BUG=
R=brucedawson@chromium.org, thestig@chromium.org

Review URL: https://codereview.chromium.org/810883005

1 files changed, 2 insertions, 2 deletions

diff --git a/core/include/fxcrt/fx_stream.h b/core/include/fxcrt/fx_stream.h
index 8e298f7727..e54af579b6 100644
--- a/core/include/fxcrt/fx_stream.h
+++ b/core/include/fxcrt/fx_stream.h
@@ -65,7 +65,7 @@ FX_BOOL		FX_File_Move(FX_WSTR fileNameSrc, FX_WSTR fileNameDst);
 class IFX_StreamWrite
 {
 public:
-
+    virtual ~IFX_StreamWrite() { }
     virtual void		Release() = 0;
 
     virtual	FX_BOOL		WriteBlock(const void* pData, size_t size) = 0;
@@ -91,6 +91,7 @@ IFX_FileWrite* FX_CreateFileWrite(FX_LPCWSTR filename);
 class IFX_StreamRead
 {
 public:
+    virtual ~IFX_StreamRead() { }
 
     virtual void			Release() = 0;
 
@@ -103,7 +104,6 @@ public:
 class IFX_FileRead : IFX_StreamRead
 {
 public:
-
     virtual void			Release() = 0;
 
     virtual FX_FILESIZE		GetSize() = 0;