Halliday & Matthiessen (2014: 536):
Where the projected clause is non-finite the Subject can be presupposed from the primary clause provided it is the participant that is actually doing the projecting – Senser or (more rarely) Sayer. So the thought of being a queen (encouraged her), her desire to be a queen ... , her assertion of being a queen ... , where ‘she’ is doing the thinking, etc.; but the news of her being a queen (proclaimed by someone else), the thought of her being a queen (in someone else’s mind), and so on. These correspond to the non-finite forms with hypotaxis: she wanted to be a queen, they wanted her to be a queen. In the finite forms, of course, the Subject is always made explicit.