Merge to XFA: Fix some -Wmaybe-uninitialized errors.

core/src/fpdfapi/fpdf_edit/fpdf_edit_image.cpp

Index: core/src/fpdfapi/fpdf_edit/fpdf_edit_image.cpp
diff --git a/core/src/fpdfapi/fpdf_edit/fpdf_edit_image.cpp b/core/src/fpdfapi/fpdf_edit/fpdf_edit_image.cpp
index 488d8393c79ce247a05560d7ea57943b1e8be741..1dd0ae6170a95bc0d14722b8de31dd584fa39513 100644
--- a/core/src/fpdfapi/fpdf_edit/fpdf_edit_image.cpp
+++ b/core/src/fpdfapi/fpdf_edit/fpdf_edit_image.cpp
@@ -218,7 +218,7 @@ void CPDF_Image::SetImage(const CFX_DIBitmap* pBitmap,
     int32_t maskWidth = pMaskBitmap->GetWidth();
     int32_t maskHeight = pMaskBitmap->GetHeight();
     uint8_t* mask_buf = NULL;
-    FX_STRSIZE mask_size;
+    FX_STRSIZE mask_size = 0;
     CPDF_Dictionary* pMaskDict = new CPDF_Dictionary;
     pMaskDict->SetAtName(FX_BSTRC("Type"), FX_BSTRC("XObject"));
     pMaskDict->SetAtName(FX_BSTRC("Subtype"), FX_BSTRC("Image"));