Fix depth-first search for Java 9 modules

To compute modules to be added to compilation roots in
JavaModuleGraph.getAllDependencies, we should look not only for
transitive requirements of root modules, but for transitive requirements
of _root modules' requirements_. The same logic applies to
JavaModuleGraph.reads. In other words, when looking for a path in the
module graph between two modules, the first edge's transitiveness
doesn't matter, but all other edges after the first must be transitive.

There was also a stupid bug in dfs in
JavaModuleGraph.getAllDependencies: we continued the DFS only if the
module _was not_ added to the "visited" set ("add" returns true if the
element was added successfully)

 #KT-18598 In Progress

compiler/testData/javaModules/unnamedReadsTransitive/moduleC/usage.kt

@@ -0,0 +1,8 @@
+import foo.*
+import bar.*
+
+fun test(): String {
+    val f = Foo()
+    val b = Bar.getFoo()
+    return "$f$b"
+}