Code cleanup and typos in trace_event [NFC]

base/trace_event/memory_tracing_observer.cc

Index: base/trace_event/memory_tracing_observer.cc
diff --git a/base/trace_event/memory_tracing_observer.cc b/base/trace_event/memory_tracing_observer.cc
index 2208cedf40f8d04d92adaccc8c6eae0b0664338f..a9659b2f81ea339557e4c7a3790728ab4c62c169 100644
--- a/base/trace_event/memory_tracing_observer.cc
+++ b/base/trace_event/memory_tracing_observer.cc
@@ -31,7 +31,7 @@ MemoryTracingObserver::MemoryTracingObserver(
     MemoryDumpManager* memory_dump_manager)
     : memory_dump_manager_(memory_dump_manager), trace_log_(trace_log) {
   // If tracing was enabled before initializing MemoryDumpManager, we missed the
-  // OnTraceLogEnabled() event. Synthetize it so we can late-join the party.
+  // OnTraceLogEnabled() event. Synthesize it so we can late-join the party.
   // IsEnabled is called before adding observer to avoid calling
   // OnTraceLogEnabled twice.
   bool is_tracing_already_enabled = trace_log_->IsEnabled();