FingerMergeFilterInterpreter: Make stricter

These changes make the filter much stricter, so that they don't
trigger on normal movement.

BUG=chromium-os:37272
TEST=Regression tests link/merge_{1..5} pass. Manual testing on device.

Change-Id: I003ff3e813216f7884dee087e93f060a39b7d135
Reviewed-on: https://gerrit.chromium.org/gerrit/43981
Commit-Queue: Andrew de los Reyes <adlr@chromium.org>
Reviewed-by: Andrew de los Reyes <adlr@chromium.org>
Tested-by: Andrew de los Reyes <adlr@chromium.org>
2 files changed