Today, --use_angle only works on macOS with the playgrounds. And it happens to be the default on macOS anyway as the default driver is broken. This makes the value of this flag somewhat dubious.

When I tried to wire this up on Windows and Linux, I ran into issues with static linking of Angle with GLFW as GLFW doesn't seem to comprehend that Angle can be linked statically.

When I tried to setup Angle to be linked dynamically, Angle was sad when compiling the Vulkan adapter (which is not needed on macOS) because of the way Flutter compiles its own VMA. When compiling statically, Angle can use our VMA. But it misses those symbols when compiling dynamically.

Either GLFW should be patched to work with a statically linked Angle or we should figure out our rules on making Angle have access to a VMA when linking dynmaically.

My preference is for the latter.