Revert of Use CopyOnWriteBuffer instead of Buffer to avoid unnecessary copies.

webrtc/base/buffer_unittest.cc

Index: webrtc/base/buffer_unittest.cc
diff --git a/webrtc/base/buffer_unittest.cc b/webrtc/base/buffer_unittest.cc
index 20b09757e1295e2f68b2473687e32f4b36f1fd79..80d26927a227c91d24ee07e389c55c9e1691e6ba 100644
--- a/webrtc/base/buffer_unittest.cc
+++ b/webrtc/base/buffer_unittest.cc
@@ -62,6 +62,23 @@
   EXPECT_EQ(buf.size(), 16u);
   EXPECT_EQ(buf.capacity(), 16u);
   EXPECT_EQ(0, memcmp(buf.data(), kTestData, 16));
+}
+
+TEST(BufferTest, TestConstructCopy) {
+  Buffer buf1(kTestData), buf2(buf1);
+  EXPECT_EQ(buf2.size(), 16u);
+  EXPECT_EQ(buf2.capacity(), 16u);
+  EXPECT_EQ(0, memcmp(buf2.data(), kTestData, 16));
+  EXPECT_NE(buf1.data(), buf2.data());
+  EXPECT_EQ(buf1, buf2);
+}
+
+TEST(BufferTest, TestAssign) {
+  Buffer buf1, buf2(kTestData, sizeof(kTestData), 256);
+  EXPECT_NE(buf1, buf2);
+  buf1 = buf2;
+  EXPECT_EQ(buf1, buf2);
+  EXPECT_NE(buf1.data(), buf2.data());
 }
 
 TEST(BufferTest, TestSetData) {