Event's identifiers are based on the naming of the storage structure

[xgreenx]

The naming of the storage structure affects event identifiers.
It means that if users are implementing the same interface, events provided by them can have different identifiers(and topics of this event too) in case of the different storage struct naming.

The solution for this can be: during the definition of events set the name of the trait which will emit these events. In this case, if users implement the IErc20 trait, events emitted by them will have the same identifiers.
But this solutions is not possible at the moment for 2 reasons:

1. We can't define events during trait definition. It is described here
2. Event doesn't allow to customize ident of storage struct/trait. But it can be easily integrated.

Also it can be part of use-ink/ink#564

[xgreenx]

Resolving of use-ink/ink#809 will resolve our issue.