Move when swapping, if possible.

include/core/SkTypes.h

Index: include/core/SkTypes.h
diff --git a/include/core/SkTypes.h b/include/core/SkTypes.h
index 0cef8a125702d6f7d3df663d7b4a5be3aa3bdabf..0a3e3ac4871b702fba2e9aa208ede0cff378b329 100644
--- a/include/core/SkTypes.h
+++ b/include/core/SkTypes.h
@@ -396,9 +396,9 @@ static inline constexpr int Sk32ToBool(uint32_t n) {
 /** Generic swap function. Classes with efficient swaps should specialize this function to take
     their fast path. This function is used by SkTSort. */
 template <typename T> inline void SkTSwap(T& a, T& b) {
-    T c(a);
-    a = b;
-    b = c;
+    T c(std::move(a));
+    a = std::move(b);
+    b = std::move(c);
 }
 
 static inline int32_t SkAbs32(int32_t value) {