BRegion: add move construction and assignment support

GCC 2 support is also provided with `MoveFrom` method.

Change-Id: Ibd062f501fdeb5538ade6c84dcafb61cff70cc32
Reviewed-on: https://review.haiku-os.org/c/haiku/+/8529
Tested-by: Commit checker robot <[email protected]>
Reviewed-by: waddlesplash <[email protected]>

headers/os/interface/Region.h

@@ -29,13 +29,20 @@ public:
 								BRegion();
 								BRegion(const BRegion& other);
 								BRegion(const BRect rect);
+#if defined(__cplusplus) && __cplusplus >= 201103L
+								BRegion(BRegion&& other);
+#endif
 	virtual						~BRegion();
 
 			BRegion&			operator=(const BRegion& other);
+#if defined(__cplusplus) && __cplusplus >= 201103L
+			BRegion&			operator=(BRegion&& other);
+#endif
 			bool				operator==(const BRegion& other) const;
 
 			void				Set(BRect rect);
 			void				Set(clipping_rect clipping);
+			void				MoveFrom(BRegion& other);
 
 			BRect				Frame() const;
 			clipping_rect		FrameInt() const;

src/kits/interface/Region.cpp

@@ -59,6 +59,19 @@ BRegion::BRegion(const BRect rect)
 }
 
 
+#if defined(__cplusplus) && __cplusplus >= 201103L
+BRegion::BRegion(BRegion&& other)
+	:
+	fCount(0),
+	fDataSize(0),
+	fBounds((clipping_rect){ 0, 0, 0, 0 }),
+	fData(NULL)
+{
+	MoveFrom(other);
+}
+#endif
+
+
 // NOTE: private constructor
 BRegion::BRegion(const clipping_rect& clipping)
 	:
@@ -95,6 +108,17 @@ BRegion::operator=(const BRegion& other)
 }
 
 
+#if defined(__cplusplus) && __cplusplus >= 201103L
+BRegion&
+BRegion::operator=(BRegion&& other)
+{
+	MoveFrom(other);
+
+	return *this;
+}
+#endif
+
+
 bool
 BRegion::operator==(const BRegion& other) const
 {
@@ -128,6 +152,30 @@ BRegion::Set(clipping_rect clipping)
 }
 
 
+void
+BRegion::MoveFrom(BRegion& other)
+{
+	if (other.CountRects() <= 0) {
+		MakeEmpty();
+		return;
+	}
+	if (other.CountRects() == 1) {
+		Set(other.FrameInt());
+		other.MakeEmpty();
+		return;
+	}
+	fCount = other.fCount;
+	fDataSize = other.fDataSize;
+	fBounds = other.fBounds;
+	fData = other.fData;
+
+	other.fCount = 0;
+	other.fDataSize = 0;
+	other.fBounds = (clipping_rect){ 0, 0, 0, 0 };
+	other.fData = NULL;
+}
+
+
 BRect
 BRegion::Frame() const
 {