[Java] JDK Collection lambda models

Adds support for data flow tracking through simple JDK collection
functional APIs.
 - `Iterable::forEach`
 - `Iterator::forEachRemaining`
 - `Map::forEach`

Replaces #5871

Signed-off-by: Jonathan Leitschuh <Jonathan.Leitschuh@gmail.com>

java/ql/test/library-tests/dataflow/collections/Test.java

@@ -25,5 +25,57 @@ public class Test {
     Iterator<String> it = m.values().iterator();
     String x5 = it.next();
     sink(x5); // Flow
+
+    it.forEachRemaining(x6 -> {
+      sink(x6); // Flow
+    });
+
+    m.forEach((x7_k, x8_v) -> {
+      sink(x7_k); // No flow
+      sink(x8_v); // Flow
+    });
+
+    m.entrySet().forEach(entry -> {
+      String x9 = entry.getKey();
+      String x10 = entry.getValue();
+      sink(x9); // No flow
+      sink(x10); // Flow
+    });    
+  }
+
+  public void run2() {
+    HashMap<String, String> m = new HashMap<>();
+
+    m.put(tainted, tainted);
+    
+    m.forEach((x11_k, x12_v) -> {
+      sink(x11_k); // Flow
+      sink(x12_v); // Flow
+    });
+
+    m.entrySet().forEach(entry -> {
+      String x13 = entry.getKey();
+      String x14 = entry.getValue();
+      sink(x13); // Flow
+      sink(x14); // Flow
+    });
+  }
+
+  public void run3() {
+    Set<String> s = new HashSet<>();
+    String x15 = s.iterator().next();
+    sink(x15); // No flow
+
+    s.forEach(x16 -> {
+      sink(x16); // No flow
+    });
+
+    s.add(tainted);
+    String x17 = s.iterator().next();
+    sink(x17); // Flow
+
+    s.forEach(x18 -> {
+      sink(x18); // Flow
+    });
   }
 }