Make the DevTools UI more dense

[kenzieschmoll]

Users can use DevTools in the browser or embedded in the IDE. Either way, a more dense UI would help with being able to see more data at once. Our flutter UI is still too "mobile-first" in some areas WRT tap target sizes, row heights, font sizes, etc.

We've had user's complain that they don't have enough screen real estate to visualize the data they are looking for (for example, wanting to be able to see the live memory chart and look at a memory profile without being constrained by screen space.)

The layout explorer is another example of a UI component that could be made considerably more dense

[kenzieschmoll]

• smaller default font size
• smaller default table row size
• smaller table header sizes
• smaller default padding sizes
• smaller default button heights / sizes

One example comparison is the Android Studio profiler vs the DevTools profiler (keep in mind the android studio screenshot is from an embedded IDE tool window and the DevTools screen is full screen on a laptop):