windowscodecs: Initialize unused part of metadata PROPVARIANT to 0.

dlls/windowscodecs/gifformat.c

@@ -75,7 +75,7 @@ static HRESULT load_LSD_metadata(IStream *stream, const GUID *vendor, DWORD opti
     hr = IStream_Read(stream, &lsd_data, sizeof(lsd_data), &bytesread);
     if (FAILED(hr) || bytesread != sizeof(lsd_data)) return S_OK;
 
-    result = HeapAlloc(GetProcessHeap(), 0, sizeof(MetadataItem) * 9);
+    result = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(MetadataItem) * 9);
     if (!result) return E_OUTOFMEMORY;
 
     for (i = 0; i < 9; i++)
@@ -180,7 +180,7 @@ static HRESULT load_IMD_metadata(IStream *stream, const GUID *vendor, DWORD opti
     hr = IStream_Read(stream, &imd_data, sizeof(imd_data), &bytesread);
     if (FAILED(hr) || bytesread != sizeof(imd_data)) return S_OK;
 
-    result = HeapAlloc(GetProcessHeap(), 0, sizeof(MetadataItem) * 8);
+    result = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(MetadataItem) * 8);
     if (!result) return E_OUTOFMEMORY;
 
     for (i = 0; i < 8; i++)
@@ -273,7 +273,7 @@ static HRESULT load_GCE_metadata(IStream *stream, const GUID *vendor, DWORD opti
     hr = IStream_Read(stream, &gce_data, sizeof(gce_data), &bytesread);
     if (FAILED(hr) || bytesread != sizeof(gce_data)) return S_OK;
 
-    result = HeapAlloc(GetProcessHeap(), 0, sizeof(MetadataItem) * 5);
+    result = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(MetadataItem) * 5);
     if (!result) return E_OUTOFMEMORY;
 
     for (i = 0; i < 5; i++)
@@ -388,7 +388,7 @@ static HRESULT load_APE_metadata(IStream *stream, const GUID *vendor, DWORD opti
         data_size += subblock_size + 1;
     }
 
-    result = HeapAlloc(GetProcessHeap(), 0, sizeof(MetadataItem) * 2);
+    result = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(MetadataItem) * 2);
     if (!result)
     {
         HeapFree(GetProcessHeap(), 0, data);
@@ -493,7 +493,7 @@ static HRESULT load_GifComment_metadata(IStream *stream, const GUID *vendor, DWO
 
     data[data_size] = 0;
 
-    result = HeapAlloc(GetProcessHeap(), 0, sizeof(MetadataItem));
+    result = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(MetadataItem));
     if (!result)
     {
         HeapFree(GetProcessHeap(), 0, data);

dlls/windowscodecs/metadatahandler.c

@@ -696,7 +696,7 @@ static HRESULT LoadUnknownMetadata(IStream *input, const GUID *preferred_vendor,
         return hr;
     }
 
-    result = HeapAlloc(GetProcessHeap(), 0, sizeof(MetadataItem));
+    result = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(MetadataItem));
     if (!result)
     {
         HeapFree(GetProcessHeap(), 0, data);
@@ -1126,7 +1126,7 @@ static HRESULT LoadIfdMetadata(IStream *input, const GUID *preferred_vendor,
         return WINCODEC_ERR_BADMETADATAHEADER;
     }
 
-    result = HeapAlloc(GetProcessHeap(), 0, count * sizeof(*result));
+    result = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, count * sizeof(*result));
     if (!result)
     {
         HeapFree(GetProcessHeap(), 0, entry);

dlls/windowscodecs/pngformat.c

@@ -111,7 +111,7 @@ static HRESULT LoadTextMetadata(IStream *stream, const GUID *preferred_vendor,
 
     value_len = data_size - name_len - 1;
 
-    result = HeapAlloc(GetProcessHeap(), 0, sizeof(MetadataItem));
+    result = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(MetadataItem));
     name = HeapAlloc(GetProcessHeap(), 0, name_len + 1);
     value = HeapAlloc(GetProcessHeap(), 0, value_len + 1);
     if (!result || !name || !value)