base: Remove the string logging from CHECK().

chrome/browser/media/webrtc/webrtc_browsertest_perf.cc

Index: chrome/browser/media/webrtc/webrtc_browsertest_perf.cc
diff --git a/chrome/browser/media/webrtc/webrtc_browsertest_perf.cc b/chrome/browser/media/webrtc/webrtc_browsertest_perf.cc
index 3a37ad321363940c91db963e018fbfa36a924e26..c90153bac9f76c196a9163f6b821307b89f4daf5 100644
--- a/chrome/browser/media/webrtc/webrtc_browsertest_perf.cc
+++ b/chrome/browser/media/webrtc/webrtc_browsertest_perf.cc
@@ -185,7 +185,8 @@ static std::string ExtractSsrcIdentifier(const std::string& key) {
   // Example key: ssrc_1234-someStatName. Grab the part before the dash.
   size_t key_start_pos = 0;
   size_t key_end_pos = key.find("-");
-  CHECK(key_end_pos != std::string::npos) << "Could not parse key " << key;
+  // Could not parse key |key|
+  CHECK(key_end_pos != std::string::npos);
   return key.substr(key_start_pos, key_end_pos - key_start_pos);
 }