Make PacketReader/PacketWriter interfaces async-only.

blimp/net/test_common.h

Index: blimp/net/test_common.h
diff --git a/blimp/net/test_common.h b/blimp/net/test_common.h
index 119f8ee1e73935318974f09c22f7326569c331c9..7705a7ed3343cbcf8576084a0339907c60298898 100644
--- a/blimp/net/test_common.h
+++ b/blimp/net/test_common.h
@@ -46,7 +46,7 @@ MATCHER_P(EqualsProto, message, "") {
 // message (type: BlimpMessage) The message to compare with |arg|.
 MATCHER_P(BufferEqualsProto, message, "") {
   BlimpMessage actual_message;
-  actual_message.ParseFromArray(arg->data(), arg->BytesRemaining());
+  actual_message.ParseFromArray(arg->data(), message.ByteSize());
   std::string expected_serialized;
   std::string actual_serialized;
   message.SerializeToString(&expected_serialized);
@@ -64,7 +64,8 @@ ACTION_TEMPLATE(FillBufferFromString,
   memcpy(testing::get<buf_idx>(args)->data(), str.data(), str.size());
 }
 
-// GMock action that writes data from a blimp message to an IOBuffer .
+// GMock action that writes data from a BlimpMessage to a GrowableIOBuffer.
+// Advances the buffer's |offset| to the end of the message.
 //
 //   buf_idx (template parameter 0): 0-based index of the IOBuffer arg.
 //   message: the blimp message containing data to be written to the IOBuffer
@@ -75,6 +76,13 @@ ACTION_TEMPLATE(FillBufferFromMessage,
                             message->ByteSize());
 }
 
+// Calls |set_offset()| for a GrowableIOBuffer.
+ACTION_TEMPLATE(SetBufferOffset,
+                HAS_1_TEMPLATE_PARAMS(int, buf_idx),
+                AND_1_VALUE_PARAMS(offset)) {
+  testing::get<buf_idx>(args)->set_offset(offset);
+}
+
 // Formats a string-based representation of a BlimpMessage header.
 std::string EncodeHeader(size_t size);
 
@@ -115,8 +123,8 @@ class MockPacketReader : public PacketReader {
   ~MockPacketReader() override;
 
   MOCK_METHOD2(ReadPacket,
-               int(const scoped_refptr<net::GrowableIOBuffer>&,
-                   const net::CompletionCallback&));
+               void(const scoped_refptr<net::GrowableIOBuffer>&,
+                    const net::CompletionCallback&));
 };
 
 class MockPacketWriter : public PacketWriter {
@@ -125,8 +133,8 @@ class MockPacketWriter : public PacketWriter {
   ~MockPacketWriter() override;
 
   MOCK_METHOD2(WritePacket,
-               int(scoped_refptr<net::DrainableIOBuffer>,
-                   const net::CompletionCallback&));
+               void(scoped_refptr<net::DrainableIOBuffer>,
+                    const net::CompletionCallback&));
 };
 
 class MockConnectionErrorObserver : public ConnectionErrorObserver {