[bindings] Remove the last traces of V8RethrowTryCatchScope from V8Binding.h
[bindings] Remove the last traces of V8RethrowTryCatchScope from V8Binding.h

CL [1] introduced the V8RethrowTryCatchScope for auto rethrowing but is no longer used.
Removing the class declaration as unused code.

If required, can be revived back by time travel in the past :)

[1] https://codereview.chromium.org/304223007

R=jl@opera.com, haraken@chromium.org

Review URL: https://codereview.chromium.org/1014003002

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@191988 bbb929c8-8fbe-4397-9dbb-9b2b20218538

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