Change selected mode to 'Manual' when preset mode is modified

User can add or delete any category record of the preset mode using
'Edit Categories'. Change the current selected recording mode to
'Manually select settings' when user modifies the default preset
recording categories set.

BUG=682
Split side panel container out of timeline_view.html file
Rename TimelineViewSidePanel to SidePanelRegistry
Merge pull request #690 from kphanee/chg_manual_mode_on_edit

Change selected mode to 'Manual' when preset mode is modified
Merge branch 'master' into rename_side_panel
Merge pull request #691 from dj2/rename_side_panel

Rename side panel classes
Revert "Enable scrollbars on traceviewer tests.html if required."
Merge pull request #697 from google/revert-686-scroll_unittest_page

Revert "Enable scrollbars on traceviewer tests.html if required."
Actually fix scrolling: the interactive_test_runner selector was broken

The reason for https://github.com/google/trace-viewer/commit/9d2402 was that
test scrolling was broken. This was reverted because the fix changed the actual
body to scroll.

The real bug was that the interactive-test-runner had lost its styling due
to a typo during the tvcm move. This caused it to not get sized,
which prevented it from overflowing, which prevented scrolling.

This fixes the styling, and everything works again.
InputLatencyTest was adding an event listener on the document, leading to flake.

Every test that ran after that point that caused a requestSelectionChanged
event would then fail.
Fix side_panel_container_test after registry refactoring
Make update_gyp_and_gn work when run relatively
Move trace_model*.html into trace_model/
cc.html -> cc/cc.html
Move cc/ to extras
Move tcmalloc and collapse/expand images to tcmalloc/
Move tcmalloc to extras
Move net to extras
move gpu to extras
Move system_stats to extras