Fix LogDog viewer in unstable Chrome.
Fix LogDog viewer in unstable Chrome.

Address a possible bug in upstream Chrome JavaScript engine that
caused incorrect binding of "this". We fix this by coding the
"appendBlock" function as a formal member function instead of an inline
arrow function.

BUG=chromium:722541
TEST=local
R=hinoka@chromium.org

Review-Url: https://codereview.chromium.org/2886873004

luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go