DevTools: Add missing scrollbar to the memory panel.

BUG=826225
NOTRY=true
TBR=caseq@chromium.org

Change-Id: I1020aac34ec1646e976b6e6688bebdecd70f8b10
Reviewed-on: https://chromium-review.googlesource.com/982152Reviewed-by: Alexei Filippov <alph@chromium.org>
Commit-Queue: Alexei Filippov <alph@chromium.org>
Cr-Commit-Position: refs/heads/master@{#546119}

third_party/WebKit/Source/devtools/front_end/profiler/profilesPanel.css

@@ -114,6 +114,7 @@
 
 .profile-launcher-view-content {
     padding: 10px 16px;
+    overflow: auto;
 }
 
 .profile-launcher-view-content h1 {