Adjust the FPS graph scale.

Instead of making the FPS graph linearly scale, scale it based on the frame length,
but show the data in terms of FPS. Because it is inversely proportional, and most
of the data never gets below 20, concentrate the axis from 20-60 FPS, since otherwise
over half of the available graph space ends up blank.

This means we should convert all of the FPS data to frame length data.

* Animometer/resources/debug-runner/graph.js: Update the domain to be based on
frame length in milliseconds instead of FPS. Update the cursor to consider all of the
values being shown, and then pick the min and max values to represent the length of the
cursor.
* Animometer/resources/runner/animometer.js:
* Animometer/resources/strings.js:
* Animometer/tests/resources/main.js:
(processSamples): Add the ability to only sample a range of the data instead of everything
after an offset index. Update sampler to record the frame lengths instead of the frame
rate.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@196292 268f45cc-cd09-0410-ab3c-d52691b4dbfc
5 files changed