Some navigation operators check flags like `RV3D_LOCK_ROTATION` in the invoke function to see if the operation can be performed. As the comment indicates, these checks should be in the poll function. This avoids redundant initialization. Note that this brings functional changes as now operators with context `EXEC_DEFAULT` will also be affected by the flag. (There doesn't seem to be a problem with the current code). Differential Revision: https://developer.blender.org/D14005