Fix gn bootstrap

R=dpranke

Change-Id: I469e7e478141e7c389f7a16a5e860122785bab44
Reviewed-on: https://chromium-review.googlesource.com/1072740Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Commit-Queue: Thomas Anderson <thomasanderson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#561663}

tools/gn/bootstrap/bootstrap.py

@@ -649,7 +649,6 @@ def write_gn_ninja(path, root_gen_dir, options, windows_x64_toolchain):
       'base/trace_event/memory_peak_detector.cc',
       'base/trace_event/memory_usage_estimator.cc',
       'base/trace_event/process_memory_dump.cc',
-      'base/trace_event/sharded_allocation_register.cc',
       'base/trace_event/trace_buffer.cc',
       'base/trace_event/trace_config.cc',
       'base/trace_event/trace_config_category_filter.cc',