Do not collapse line numbers that are indicated in the URL

When users navigate to the diff view with a line number specified at the
end, depending on their context preference, the line might be in a
shared region that gets collapsed when the diff renders. With this
change, the location specified in the URL is prevented from being
collapsed by marking it as a "key" location.

Bug: Issue 5247
Change-Id: Ifd5827cd922b022cddb1601911a9ecea6a054f35
diff --git a/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.html b/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.html
index 532b928..dbb058a 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.html
@@ -272,7 +272,8 @@
               is-image-diff="[[isImageDiff]]"
               base-image="[[_baseImage]]"
               revision-image="[[_revisionImage]]"
-              parent-index="[[_parentIndex]]">
+              parent-index="[[_parentIndex]]"
+              line-of-interest="[[lineOfInterest]]">
             <table
                 id="diffTable"
                 class$="[[_diffTableClass]]"