| The ExecutionContextPriorityDecorator is responsible for assigning the priority |
| of all the frames and workers in the graph. |
| |
| This is done through a system of voting where each voter can increase the |
| priority of an execution context independently, and the vote with the highest |
| priority determines which priority the given frame or worker will be assigned. |
| |
| The RootVoteObserver is a simple layer on top of the voting system that receives |
| the final vote for an execution context and does the actual assignment to the |
| graph node. |
| |
| Each voter tracks a single property of an execution context and casts their vote |
| via their voting channel to the MaxVoteAggregator. |
| |
| A notable exception is the AdFrameVoter, which casts a "negative" vote which can |
| reduce the priority of an execution context by overriding the vote of all the |
| other voters. |
