Fix a bunch of -Wunused-but-set-variable warnings.

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 3a3756de5d748c563f95890edf89fa732b12f71d..a316296d5a757d4c3638a036ff33856ce8181009 100644
--- a/core/src/fpdfapi/fpdf_edit/fpdf_edit_image.cpp
+++ b/core/src/fpdfapi/fpdf_edit/fpdf_edit_image.cpp
@@ -210,7 +210,6 @@ void CPDF_Image::SetImage(const CFX_DIBitmap* pBitmap, FX_INT32 iCompress, IFX_F
         FX_INT32 maskHeight = pMaskBitmap->GetHeight();
         FX_LPBYTE mask_buf = NULL;
         FX_STRSIZE mask_size;
-        FX_BOOL bDeleteMask = TRUE;
         CPDF_Dictionary* pMaskDict = new CPDF_Dictionary;
         pMaskDict->SetAtName(FX_BSTRC("Type"), FX_BSTRC("XObject"));
         pMaskDict->SetAtName(FX_BSTRC("Subtype"), FX_BSTRC("Image"));
@@ -243,7 +242,6 @@ void CPDF_Image::SetImage(const CFX_DIBitmap* pBitmap, FX_INT32 iCompress, IFX_F
             }
             pMaskStream = new CPDF_Stream(mask_buf, mask_size, pMaskDict);
             m_pDocument->AddIndirectObject(pMaskStream);
-            bDeleteMask = FALSE;
             pDict->SetAtReference(FX_BSTRC("SMask"), m_pDocument, pMaskStream);
         }
         if (pBitmap->HasAlpha()) {

[Tom Sepez, 2015/04/17 16:20:16]

This duplicates the test that lead to the allocation above, and feels fragile. 
I'd do the following:
1. rename bDeleteMask to bDeleteMaskBitmap since there are other mask_* locals
here.
2. Declare and set bDeleteMask to FALSE at line 198 at the same time we declare
pMaskBitmap.
3. set pMaskBitmap to TRUE at line 200
4. test pDeleteMaskBitmap here instead of the hasalpha.