- added Browser.isHiDPIAware flag that gets initialized from Module.isHiDPIAware
- from the webgpu samples (https://webgpu.github.io/webgpu-samples/samples/helloTriangle), the gist of the logic is to scale canvas.width (resp. canvas.height) by the devicePixelRatio and set canvas.clientWidth to the width
- coordinates are then scaled down to reflect what the client is expecting

- calling Browser.requestFullscreen raises "Failed to execute 'requestFullscreen' on 'Element': API can only be initiated by a user gesture"

- handle case where the canvas size is fixed (default shell)
- handle case where request full screen is issued by the user (default shell)

- created issue emscripten-core#20600 to implement in a separate PR

- the rationale is that the client can simply call Module.setHiDPIAware based on the needs

- ironically, although the call was wrong, it ended up doing the right thing...

# Conflicts:
#	src/library_glfw.js

# Conflicts:
#	src/library_browser.js

- mocking devicePixelRatio allow to write a comprehensive test
- added handling dynamic changes to devicePixelRatio by installing a listener

- unclear why it works locally

# Conflicts:
#	src/library_glfw.js

- Browser.setCanvasSize sets win.width and win.height already so it should not be overridden afterwards
- Browser.setCanvasSize also triggers the win.windowSizeFunc callback when appropriate (window size has actually changed)

- now GLFW use GLFW_SCALE_TO_MONITOR during window creation to determine hi dpi awareness
- Module.setHiDPIAware is only set when using GLFW (making sure that other platforms don't accidentally use it)

- removed function from module
- simply use glfwSetWindowAttrib instead

# Conflicts:
#	src/library_glfw.js