base: Remove the string logging from CHECK().

components/metrics/leak_detector/leak_detector.cc

Index: components/metrics/leak_detector/leak_detector.cc
diff --git a/components/metrics/leak_detector/leak_detector.cc b/components/metrics/leak_detector/leak_detector.cc
index 800ff3b00cd99085fc406c75714d3c0c8363fd5a..c2daa5eeb2c069358a09bcba987dfd5c3d684cf7 100644
--- a/components/metrics/leak_detector/leak_detector.cc
+++ b/components/metrics/leak_detector/leak_detector.cc
@@ -194,7 +194,8 @@ void LeakDetector::Init(const MemoryLeakReportProto::Params& params,
 
   // The initialization should be done only once. Check for this by examining
   // whether |impl_| has already been initialized.
-  CHECK(!impl_.get()) << "Cannot initialize LeakDetector more than once!";
+  // Cannot initialize LeakDetector more than once!
+  CHECK(!impl_.get());
   impl_.reset(new leak_detector::LeakDetectorImpl(
       mapping.addr, mapping.size, params.size_suspicion_threshold(),
       params.call_stack_suspicion_threshold()));