* extract code for displaying graphs and managing graph drilldowns from *Frontend classes (which also manage the graph setup UI) into separate Plot classes (a Plot class and two subclasses, MetricsPlot and MachineQualHistogram).  eventually, these plot classes will be usable as embedded widgets in other pages.
* made some changes to graphing_utils.py to support the new design, including encoding drilldown information with JSONEncoder
* extract GraphingDialog class to a generic, top-level SimpleDialog class, so that it'll be usable from embedded widgets without including all the frontend code
* fix a bug in FilterSelector.isEmpty() (it would always return false previously)
* fix a bug in TableView where no column would be sorted on in some cases

Signed-off-by: Steve Howard <showard@google.com>


git-svn-id: http://test.kernel.org/svn/autotest/trunk@2990 592f7852-d20e-0410-864c-8624ca9c26a4
12 files changed