Delete StringStream class, used in LogTest.

Drops another dependency on the Stream interface.

Bug: webrtc:6424
Change-Id: Id6d2d72f20bab0df067d0e2f0413be6eb78a58ce
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/213147
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Commit-Queue: Niels Moller <nisse@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#33582}
diff --git a/rtc_base/logging_unittest.cc b/rtc_base/logging_unittest.cc
index 6bb20ab..225d66d 100644
--- a/rtc_base/logging_unittest.cc
+++ b/rtc_base/logging_unittest.cc
@@ -20,94 +20,23 @@
 #include "rtc_base/checks.h"
 #include "rtc_base/event.h"
 #include "rtc_base/platform_thread.h"
-#include "rtc_base/stream.h"
 #include "rtc_base/time_utils.h"
 #include "test/gtest.h"
 
 namespace rtc {
 
-namespace {
-
-class StringStream : public StreamInterface {
+class LogSinkImpl : public LogSink {
  public:
-  explicit StringStream(std::string* str);
-  explicit StringStream(const std::string& str);
-
-  StreamState GetState() const override;
-  StreamResult Read(void* buffer,
-                    size_t buffer_len,
-                    size_t* read,
-                    int* error) override;
-  StreamResult Write(const void* data,
-                     size_t data_len,
-                     size_t* written,
-                     int* error) override;
-  void Close() override;
-
- private:
-  std::string& str_;
-  size_t read_pos_;
-  bool read_only_;
-};
-
-StringStream::StringStream(std::string* str)
-    : str_(*str), read_pos_(0), read_only_(false) {}
-
-StringStream::StringStream(const std::string& str)
-    : str_(const_cast<std::string&>(str)), read_pos_(0), read_only_(true) {}
-
-StreamState StringStream::GetState() const {
-  return SS_OPEN;
-}
-
-StreamResult StringStream::Read(void* buffer,
-                                size_t buffer_len,
-                                size_t* read,
-                                int* error) {
-  size_t available = std::min(buffer_len, str_.size() - read_pos_);
-  if (!available)
-    return SR_EOS;
-  memcpy(buffer, str_.data() + read_pos_, available);
-  read_pos_ += available;
-  if (read)
-    *read = available;
-  return SR_SUCCESS;
-}
-
-StreamResult StringStream::Write(const void* data,
-                                 size_t data_len,
-                                 size_t* written,
-                                 int* error) {
-  if (read_only_) {
-    if (error) {
-      *error = -1;
-    }
-    return SR_ERROR;
-  }
-  str_.append(static_cast<const char*>(data),
-              static_cast<const char*>(data) + data_len);
-  if (written)
-    *written = data_len;
-  return SR_SUCCESS;
-}
-
-void StringStream::Close() {}
-
-}  // namespace
-
-template <typename Base>
-class LogSinkImpl : public LogSink, public Base {
- public:
-  LogSinkImpl() {}
+  explicit LogSinkImpl(std::string* log_data) : log_data_(log_data) {}
 
   template <typename P>
-  explicit LogSinkImpl(P* p) : Base(p) {}
+  explicit LogSinkImpl(P* p) {}
 
  private:
   void OnLogMessage(const std::string& message) override {
-    static_cast<Base*>(this)->WriteAll(message.data(), message.size(), nullptr,
-                                       nullptr);
+    log_data_->append(message);
   }
+  std::string* const log_data_;
 };
 
 class LogMessageForTesting : public LogMessage {
@@ -145,7 +74,7 @@
   int sev = LogMessage::GetLogToStream(nullptr);
 
   std::string str;
-  LogSinkImpl<StringStream> stream(&str);
+  LogSinkImpl stream(&str);
   LogMessage::AddLogToStream(&stream, LS_INFO);
   EXPECT_EQ(LS_INFO, LogMessage::GetLogToStream(&stream));
 
@@ -207,7 +136,7 @@
   int sev = LogMessage::GetLogToStream(nullptr);
 
   std::string str1, str2;
-  LogSinkImpl<StringStream> stream1(&str1), stream2(&str2);
+  LogSinkImpl stream1(&str1), stream2(&str2);
   LogMessage::AddLogToStream(&stream1, LS_INFO);
   LogMessage::AddLogToStream(&stream2, LS_VERBOSE);
   EXPECT_EQ(LS_INFO, LogMessage::GetLogToStream(&stream1));
@@ -256,7 +185,7 @@
   thread3.Start();
 
   std::string s1, s2, s3;
-  LogSinkImpl<StringStream> stream1(&s1), stream2(&s2), stream3(&s3);
+  LogSinkImpl stream1(&s1), stream2(&s2), stream3(&s3);
   for (int i = 0; i < 1000; ++i) {
     LogMessage::AddLogToStream(&stream1, LS_WARNING);
     LogMessage::AddLogToStream(&stream2, LS_INFO);
@@ -303,7 +232,7 @@
 #if defined(WEBRTC_ANDROID)
 TEST(LogTest, CheckTagAddedToStringInDefaultOnLogMessageAndroid) {
   std::string str;
-  LogSinkImpl<StringStream> stream(&str);
+  LogSinkImpl stream(&str);
   LogMessage::AddLogToStream(&stream, LS_INFO);
   EXPECT_EQ(LS_INFO, LogMessage::GetLogToStream(&stream));
 
@@ -316,7 +245,7 @@
 // Test the time required to write 1000 80-character logs to a string.
 TEST(LogTest, Perf) {
   std::string str;
-  LogSinkImpl<StringStream> stream(&str);
+  LogSinkImpl stream(&str);
   LogMessage::AddLogToStream(&stream, LS_VERBOSE);
 
   const std::string message(80, 'X');
@@ -336,7 +265,6 @@
   finish = TimeMillis();
 
   LogMessage::RemoveLogToStream(&stream);
-  stream.Close();
 
   EXPECT_EQ(str.size(), (message.size() + logging_overhead) * kRepetitions);
   RTC_LOG(LS_INFO) << "Total log time: " << TimeDiff(finish, start)
@@ -348,7 +276,7 @@
 TEST(LogTest, EnumsAreSupported) {
   enum class TestEnum { kValue0 = 0, kValue1 = 1 };
   std::string str;
-  LogSinkImpl<StringStream> stream(&str);
+  LogSinkImpl stream(&str);
   LogMessage::AddLogToStream(&stream, LS_INFO);
   RTC_LOG(LS_INFO) << "[" << TestEnum::kValue0 << "]";
   EXPECT_NE(std::string::npos, str.find("[0]"));
@@ -356,7 +284,6 @@
   RTC_LOG(LS_INFO) << "[" << TestEnum::kValue1 << "]";
   EXPECT_NE(std::string::npos, str.find("[1]"));
   LogMessage::RemoveLogToStream(&stream);
-  stream.Close();
 }
 
 TEST(LogTest, NoopSeverityDoesNotRunStringFormatting) {