Remove cpu_profiler tracing category

The cpu_profiler category is disabled by default.
This entry is not useful and is adding confusion
to users when reporting traces on bugs.

R=oysteine@chromium.org

Change-Id: I8d272dccf9307739d8cb5d95aa830357219ae31f
Reviewed-on: https://chromium-review.googlesource.com/c/1435747Reviewed-by: oysteine <oysteine@chromium.org>
Commit-Queue: Etienne Bergeron <etienneb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#626177}

base/trace_event/builtin_categories.h

@@ -51,7 +51,6 @@
   X("cma")                                                               \
   X("compositor")                                                        \
   X("content")                                                           \
-  X("cpu_profiler")                                                      \
   X("devtools")                                                          \
   X("devtools.timeline")                                                 \
   X("devtools.timeline.async")                                           \

components/tracing/common/native_stack_sampler_android.cc

@@ -25,7 +25,8 @@ NativeStackSamplerAndroid::RecordStackFrames(
   if (!unwinder_.is_initialized()) {
     // May block on disk access. This function is executed on the profiler
     // thread, so this will only block profiling execution.
-    TRACE_EVENT0("cpu_profiler", "StackUnwinderAndroid::Initialize");
+    TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("cpu_profiler"),
+                 "StackUnwinderAndroid::Initialize");
     unwinder_.Initialize();
   }
   const void* pcs[kMaxFrameDepth];