Make all fields of inspector view (details tab, clipstack tab, geometry
view) update the correct info when user selects a draw command. Also
update the info regardless if the painting is paused or not.
Current clip and matrix will not update consistently even after this
patch, as they depend on stateful debug canvas draw (may be fixed
later).
Review URL: https://codereview.chromium.org/835903002
Make draw command image widget resize. The widget was not resizing,
effectively preventing the window from being resized smaller.
Make the rasterized draw command image be proportional to the widget
size. The draw rasterization canvas is still an equilateral rectangle
with dimensions of the smaller side of the widget.
Makes the widget re-rasterize the image only when the draw command
changes, not for each widget paint.
Renames the widget from "image widget" to "draw command geometry
widget".
Makes the background of the image black, similar to the raster widget
background.
Adds a tooltip saying "Command geometry" for the widget, so that user might
understand what the contents should be.
This commit is part of work that tries to make the debugger window to be
a bit more resizeable, so that it would fit 1900x1200 screen.
Review URL: https://codereview.chromium.org/787143004
