V1: Validation Performance issue - revalidating too much.

[markwpearce]

In a test project, I'm finding that re-validation is taking longer than it used to. This is happening with v1 (current commit a194c3925)

Changing the content of a string (something that basically shouldn't cause ANY re-validation) in the source scope is about 700 ms of validation time:

[10:15:17:589 AM][INFO ] [prj0] Program.validate metrics:
    wait for previous run---------------------------------------------------- 000.003ms,   1 calls
    before and on programValidate-------------------------------------------- 000.079ms,   1 calls
    addDeferredComponentTypeSymbolCreation----------------------------------- 001.763ms,   2 calls
    addComponentReferenceTypes----------------------------------------------- 000.125ms,   1 calls
    beforeFileValidate------------------------------------------------------- 000.005ms,   2 calls
    onFileValidate----------------------------------------------------------- 000.482ms,   2 calls
    afterFileValidate-------------------------------------------------------- 002.009ms,   2 calls
    Build component types for any component that changes--------------------- 293.115ms,   1 calls
    track and update type-time and runtime symbol dependencies and changes--- 000.018ms,   1 calls
    tracks changed symbols and prepares files and scopes for validation.----- 430.574ms,   1 calls
    invalidate affected scopes----------------------------------------------- 000.456ms,   3 calls
    validate scopes---------------------------------------------------------- 000.064ms, 143 calls
    validate scope----------------------------------------------------------- 010.084ms, 143 calls
    afterScopeValidate------------------------------------------------------- 000.049ms, 122 calls
    detect duplicate component names----------------------------------------- 000.190ms,   1 calls
    Total-------------------------------------------------------------------- 739.016ms,          

The Build component types for any component that changes and tracks changed symbols and prepares files and scopes for validation steps are taking MUCH longer than they should.