By refactoring TldSpecificLogicProxy (and renaming it to DomainPricingLogic) into
a FlowScope object that is injected into each flow, we can further inject a
DomainPricingCustomLogic into the pricer, which has hooks into each pricing
calls, e. g. getCreatePrice(), getRenewPrice(), etc.
The benefit of these customization hooks is that methods like getCreatePrice()
get called in multiple flows, such as DomainAllocateFlow,
DomainApplicationCreateFlow, and DomainCreateFlow. By customizing the return
value of getCreatePrice() itself, all of its callers gets the amended price.
This CL only includes the basic infrastructure needed, with no actual hooks
placed into each flow.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=140616990
