DevTools: Fix hitCount calculation for CPU profiles.
DevTools: Fix hitCount calculation for CPU profiles.

BUG=890467

Change-Id: Ie0e7fc413c068a83c9e225c63bc3e3abdebf3120
Reviewed-on: https://chromium-review.googlesource.com/1252636
Commit-Queue: Alexei Filippov <52e51c43e283548b762e3c9dd9a4600768db9fb4@chromium.org>
Reviewed-by: Aleksey Kozyatinskiy <562acbea96970f508ad9f5cc9fc7c62d82dd3ef8@chromium.org>
Reviewed-by: Paul Irish <5f672bbedd2fccb2b3e838838e74ef989148de66@chromium.org>
Cr-Original-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#595536}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: d6f045cfbb2b18a0d93783eb57c065f5acea7e6b
ChromeDevTools/devtools-frontend,ChromeDevTools/devtools-frontend,dart-archive/devtools-frontend,ChromeDevTools/devtools-frontend,dart-archive/devtools-frontend,ChromeDevTools/devtools-frontend,dart-archive/devtools-frontend,ChromeDevTools/devtools-frontend,dart-archive/devtools-frontend,dart-archive/devtools-frontend,ChromeDevTools/devtools-frontend,dart-archive/devtools-frontend