filter: PPT import: PptPlaceholder is 1 byte large

The array of 8 bytes corresponds to 8 enum values and is read directly
in ReadPptSlideLayoutAto(); this was wrongly converted to enum.

(regression from e5a03da8)

Change-Id: I5757e06459467b3c84c4a404493fa3be23e4e9a0

filter/source/msfilter/svdfppt.cxx

@@ -309,6 +309,7 @@ SvStream& ReadPptSlideLayoutAtom( SvStream& rIn, PptSlideLayoutAtom& rAtom )
     sal_Int32 nTmp;
     rIn.ReadInt32(nTmp);
     rAtom.eLayout = static_cast<PptSlideLayout>(nTmp);
+    static_assert(sizeof(rAtom.aPlaceholderId) == 8, "wrong size of serialized array");
     rIn.Read( rAtom.aPlaceholderId, 8 );
     return rIn;
 }

include/filter/msfilter/svdfppt.hxx

@@ -58,7 +58,7 @@ class PPTTextObj;
 class DffRecordHeader;
 class SvxBulletItem;
 enum class PptSlideLayout;
-enum class PptPlaceholder;
+enum class PptPlaceholder : sal_uInt8;
 
 #define PPT_IMPORTFLAGS_NO_TEXT_ASSERT  1
 
@@ -1456,7 +1456,7 @@ enum class PptSlideLayout
 };
 
 // the following table describes the placeholder id's (values from reality followed by values taken from the documentation)
-enum class PptPlaceholder
+enum class PptPlaceholder : sal_uInt8
 {
     NONE                   = 0,   //  0 None
     MASTERTITLE            = 1,   //  1 Master title