Remove Http2String wrapper for std::string.

gfe-relnote: n/a, no functional change.
PiperOrigin-RevId: 263816460
Change-Id: I4f365540414e6a3d78fd00ce6b39a4cdd4c14140
diff --git a/http2/hpack/decoder/hpack_block_decoder_test.cc b/http2/hpack/decoder/hpack_block_decoder_test.cc
index fce45b2..4988b5c 100644
--- a/http2/hpack/decoder/hpack_block_decoder_test.cc
+++ b/http2/hpack/decoder/hpack_block_decoder_test.cc
@@ -7,6 +7,7 @@
 // Tests of HpackBlockDecoder.
 
 #include <cstdint>
+#include <string>
 
 #include "testing/gtest/include/gtest/gtest.h"
 #include "net/third_party/quiche/src/http2/decoder/decode_buffer.h"
@@ -67,14 +68,14 @@
   AssertionResult DecodeHpackExampleAndValidateSeveralWays(
       Http2StringPiece hpack_example,
       Validator validator) {
-    Http2String input = HpackExampleToStringOrDie(hpack_example);
+    std::string input = HpackExampleToStringOrDie(hpack_example);
     DecodeBuffer db(input);
     return DecodeAndValidateSeveralWays(&db, validator);
   }
 
   uint8_t Rand8() { return Random().Rand8(); }
 
-  Http2String Rand8String() { return Random().RandString(Rand8()); }
+  std::string Rand8String() { return Random().RandString(Rand8()); }
 
   HpackBlockCollector collector_;
   HpackEntryDecoderVLoggingListener listener_;
@@ -157,7 +158,7 @@
 }
 // http://httpwg.org/specs/rfc7541.html#rfc.section.C.3.1
 TEST_F(HpackBlockDecoderTest, SpecExample_C_3_1) {
-  Http2String example = R"(
+  std::string example = R"(
       82                                      | == Indexed - Add ==
                                               |   idx = 2
                                               | -> :method: GET
@@ -191,7 +192,7 @@
 
 // http://httpwg.org/specs/rfc7541.html#rfc.section.C.5.1
 TEST_F(HpackBlockDecoderTest, SpecExample_C_5_1) {
-  Http2String example = R"(
+  std::string example = R"(
       48                                      | == Literal indexed ==
                                               |   Indexed name (idx = 8)
                                               |     :status