Assorted problems with type annotations on many language model elements.

These issues are found by using 9b60 JDK to run Java8ElementTests suite
of ECJ: The assignee of this task may want to split the tasks into unit level
tickets or in some cases close them as duplicates of existing defects.

(Type is a type annotation)

(1) Given the following snippet:

 @Deprecated @Type("m") String foo() {
  return null;
 }

if method is the ExecutableElement for foo(), then

method.getReturnType().getAnnotation(Type.class) comes out as null.

(2) Given,

@Type("f") String _field = null;

if field is the VariableElement for _field

then

field.asType().getAnnotation(Type.class) comes out as null.

(3) Given:

public <@Type("mp1") T, @Type("mp2") U> void foo() {}

and typeParam is the TypeParameterElement for T then

typeParam.asType().getAnnotationMirrors() is 0, should be 1.

(4) Same problem as (3) for a generic class's type parameter.

(5) Given:

public static void main(String[] args) {}

if main is the ExecutableElement for main(), then

main.getReceiverType() should not be null, but is null.

I believe it should answer a type mirror which should return TypeKind.NONE for getKind().

Likewise these assertions should not fail, but they do.

        ExecutableType type = (ExecutableType) main.asType();
        typeMirror = type.getReceiverType();
        assertNotNull("TypeMirror should not be null", typeMirror);
        assertSame("Should be no type", TypeKind.NONE, typeMirror.getKind());


(6) Same problem as (5) for constructors seen with:

public class X {
    public X(){}
}

Also these assertions should not fail, but they do:

(where constr is the ExecutableElement for the constructor)

        type = (ExecutableType) constr.asType();
        typeMirror = type.getReceiverType();
        assertNotNull("TypeMirror should not be null", typeMirror);
        assertSame("Should be no type", TypeKind.NONE, typeMirror.getKind());

(7) Problem seen with repeating annotations on type parameter:

Given:
@Target({ElementType.TYPE_USE, ElementType.TYPE_PARAMETER }) @interface MarkerContainer {Marker[] value();}
@Repeatable(MarkerContainer .class)
@Target({ElementType.TYPE_USE, ElementType.TYPE_PARAMETER }) @interface Marker {}


class Test {
     <@Marker() @Marker() T> T foo() { return null; }
}

public class TypeParameterTest {
}

if tParam is the TypeParameterElement for foo()'s type variable T, then
tParam.getAnnotationMirrors() returns nothing, it should return
"@MarkerContainer(value=[@targets.model8.a.Marker, @targets.model8.a.Marker])"}

(8) I found it difficult to come up with a test that without borrowing significant chunks of code
from ECJ suites, so here is a description instead: If in round 0, a package-info.class gets
generated, then the subsequent round's roundEnv.getRootElements() should contain the
PackageElement, it does not seem to.

(9) Given:

package org.eclipse.jdt.compiler.apt.tests.annotations;
import java.lang.annotation.Repeatable;

@Repeatable(FooContainer.class)
public @interface Foo {
    // ...
}

and

public @interface FooContainer {
    Foo [] value();
}

some source being:

@Foo
public class JEP120_5 {
    @TFoo @TFoo @Foo String field;
}

and field being the VariableElement that corresponds to field

then:

TypeMirror mirror = field.asType();
annot = mirror.getAnnotation(TFooContainer.class);
assertNotNull("Container missing", annot);

this assertion fails.

Also
mirror.getAnnotationsByType(TFooContainer.class); is empty.

Also
mirror.getAnnotationsByType(TFoo.class); should return 2, but does not