FULL PRODUCT VERSION :
javac 1.8.0

A DESCRIPTION OF THE PROBLEM :
The source code indicated below no longer compiles in jdk8, but jdk7u51 compiled successfully as expected.

The reason is a wrong accessibility check on the method Inner.iterator() inherited from Iterable.iterator().
As per JLS 6.6, Inner.iterator() is accessible from OuterImpl because:
1. Inner.iterator() is public;
2. Inner is accessible from OuterImpl because:
2a. Inner is protected and declared by Outer;
2b. OuterImpl is a subclass of Outer.

REGRESSION.  Last worked in version 7u51

ADDITIONAL REGRESSION INFORMATION: 
javac 1.7.0_51

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Compile with the two versions of javac and notice the difference. Note: specifying -source 7 with javac version 8 does not work.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The sources should compile normally.
ACTUAL -
The compilation fails with the following message:
error: iterator() in Iterable is defined in an inaccessible class or interface
            for (Something st : inner)
  where T is a type-variable:
    T extends Object declared in interface Iterable

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
// File a/Something.java
package a;
public class Something { }

// File a/Outer.java
package a;
public class Outer {
    protected abstract class Inner implements Iterable<Something> { }
}

// File b/Client.java
package b;
import a.*;
public class Client {
    private static class OuterImpl extends Outer {
        public void method(Inner inner) {
            for (Something st : inner)
                System.out.println(st); // or anything else
        }
    }
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Workaround 1:
Cast "inner" (after the colon in the enhancer for) to Iterable<Something>.

Workaround 2:
Manually desugar the enhanced for.