A number of classes used in PolyGerrit are defined in vanilla JS files
that are included multiple times by various elements. For example,
gr-diff-line.js is included by the gr-diff-builder and by gr-diff
elements. Adds #ifndef-style guards to each of these libraries to
prevent redefinition and avoid different elements potentially referring
to different versions of the same class.
Change-Id: I45e3ba425a59989b328475b1fe58fd9f350c8ae0
Fixing UI data pipe line, re-rendering:
- store section DOM Elements in gr-diff-builder
- find diff section by line range
- store collapsed lines as gr-diff-group
- update gr-diff-builder's data model on expanding collapsed lines
- .right/.left CSS classes applied to td.lineNum instead of .content
Feature: Issue 3910
Change-Id: Ia0cb78aa00cfd910d186a37631fe71a89204a843
