fix PTBKey updateWhenSettingTypeAnnotations

Changing PTBKey.arguments[idx] changes PTBKey.equals() and
PTBKey.hashCode().
So the old PTBKey has to be removed and a new has to be inserted.
It was wrong to keep the PTBKey in hashedParameterizedTypes. Found by
codereview. It is not clear if that could produce an error other then
having bad performance by having garbage entries in the HashMap that
could furthermore not found because the hash/equals contract was
violated.

Code is executed for example during
compiler.apt.tests.Java8ElementsTests.testTypeAnnotations()

relates to
eclipse-jdt#3412

org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/lookup/TypeSystem.java

@@ -94,9 +94,10 @@ public PTBKey(ReferenceBinding type, TypeBinding[] arguments, ReferenceBinding e
 								TypeVariableBinding typeVariableBinding = (TypeVariableBinding) argument;
 								Consumer<TypeVariableBinding> previousConsumer = typeVariableBinding.updateWhenSettingTypeAnnotations;
 								typeVariableBinding.updateWhenSettingTypeAnnotations = (newTvb) -> {
-									// update the TVB argument and simulate a re-hash:
-									ParameterizedTypeBinding[] value = HashedParameterizedTypes.this.hashedParameterizedTypes.get(this);
-									arguments[idx] = newTvb;
+									// Changing arguments[idx] changes PTBKey.equals() and PTBKey.hashCode().
+									// So the old PTBKey has to be removed and a new has to be inserted:
+									ParameterizedTypeBinding[] value = HashedParameterizedTypes.this.hashedParameterizedTypes.remove(this);
+									this.arguments[idx] = newTvb;
 									HashedParameterizedTypes.this.hashedParameterizedTypes.put(this, value);
 									// for the unlikely case of multiple PTBKeys referring to this TVB chain to the next consumer:
 									if (previousConsumer != null)