(patch co-reviewed by Nathan Letwory)
Overview: GHOST using rawinput for keyboard input. GHOST window receives WM_INPUT only when it is the active window. Child window cannot be active, so when embedding blenderplayer, WM_INPUT is consumed by top level parent window (for Burster it is the web browser window). Patch register raw input device as 'inputsink' - it makes GHOST window receives all keyboard messages. Window procedure check if GHOST window is active or focused.
::TranslateMessage(&msg) generates WM_CHAR etc. messages from WM_KEYDOWN, WM_KEYUP etc. Because of using RawInput only WM_INPUT messages are processed, so we doesn't need WM_CHAR, WM_KEYDOWN etc. [this is why ::TranslateMessage is no longer getting called].
Note: It's responsibility of the parent window (aka the wrapper) to send WM_SETFOCUS to child window (embedded blenderplayer).
However some parent windows (e.g. webbrowsers) will not send WM_SETFOCUS to the child window when someone clicks on it.
In those cases the blenderplayer needs to be patched to call setFocus(&msg); in the event of WM_LBUTTONDOWN (see GHOST_SystemWin32.cpp)
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