Refactor net tests to use GMock matchers for checking net::Error results

net/http/http_chunked_decoder_unittest.cc

Index: net/http/http_chunked_decoder_unittest.cc
diff --git a/net/http/http_chunked_decoder_unittest.cc b/net/http/http_chunked_decoder_unittest.cc
index 2cd4fc172d3d5b6eb76c6ed7a995ea7658bbaa25..dd901a94ce8383dc9ab9629bd9ef1899719b92d9 100644
--- a/net/http/http_chunked_decoder_unittest.cc
+++ b/net/http/http_chunked_decoder_unittest.cc
@@ -7,8 +7,13 @@
 #include <memory>
 
 #include "net/base/net_errors.h"
+#include "net/test/gtest_util.h"
+#include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
+using net::test::IsError;
+using net::test::IsOk;
+
 namespace net {
 
 namespace {
@@ -49,7 +54,7 @@ void RunTestUntilFailure(const char* const inputs[],
     std::string input = inputs[i];
     int n = decoder.FilterBuf(&input[0], static_cast<int>(input.size()));
     if (n < 0) {
-      EXPECT_EQ(ERR_INVALID_CHUNKED_ENCODING, n);
+      EXPECT_THAT(n, IsError(ERR_INVALID_CHUNKED_ENCODING));
       EXPECT_EQ(fail_index, i);
       return;
     }