don't use indirect ref to flags

Signed-off-by: Xintao <[email protected]>

Author: hunterlxt

src/call/mod.rs

@@ -616,12 +616,12 @@ impl WriteFlags {
     }
 
     /// Get whether buffer hint is enabled.
-    pub fn get_buffer_hint(&self) -> bool {
+    pub fn get_buffer_hint(self) -> bool {
         (self.flags & grpc_sys::GRPC_WRITE_BUFFER_HINT) != 0
     }
 
     /// Get whether compression is disabled.
-    pub fn get_force_no_compress(&self) -> bool {
+    pub fn get_force_no_compress(self) -> bool {
         (self.flags & grpc_sys::GRPC_WRITE_NO_COMPRESS) != 0
     }
 }
@@ -679,8 +679,7 @@ impl SinkBase {
         }
 
         ser(t, &mut self.buffer);
-        let hint = flags.get_buffer_hint();
-        self.last_buf_hint &= hint;
+        self.last_buf_hint &= flags.get_buffer_hint();
         self.buf_flags = Some(flags);
 
         // If sink disable batch, start sending the message in buffer immediately.