Description:
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`yield from` seems to sometimes be executing the incorrect catch block when handling exceptions. When the exception is thrown during the execution of the generator, rather than as an explicit `throw()` call, it seems that sometimes catch blocks from calling frames can be skipped.

Test script:
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There are two scripts which exhibit incorrect behavior.

1) https://3v4l.org/KLdee

In this example, notice the catch block in `bar()` is executed, when really the exception happened inside of the `yield from` in the try block, so the catch block in `foo()` should be executed.

2) https://3v4l.org/oMdRC

In this example (which is only different from the previous example by the addition of the `yield 1` in `foo()` and an equivalent `next()` in `bar()`), notice that neither of the exception handlers are called.

Expected result:
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For both 1) and 2)

Starting bar()
Constructing new FooBar
Destructing FooBar
[foo()] Caught Exception
NULL
Unsetting $x
Finishing bar()

Actual result:
--------------
1)

Starting bar()
Constructing new FooBar
Destructing FooBar
[bar()] Caught Exception
Unsetting $x
Finishing bar()

2)

Starting bar()
Constructing new FooBar
Destructing FooBar

Fatal error: Uncaught Exception in /in/oMdRC:6
Stack trace:
#0 [internal function]: FooBar->current()
#1 /in/oMdRC(26): Generator->next()
#2 /in/oMdRC(37): bar()
#3 {main}
  thrown in /in/oMdRC on line 6

Process exited with code 255.