project model: report error and remove remaining RootProvider's listeners when project is closed (IDEA-171323)

This doesn't fix the real problem but may help to diagnose it and fixes the memory leak.

platform/lang-impl/src/com/intellij/openapi/roots/impl/ProjectRootManagerComponent.java

@@ -16,6 +16,7 @@
 package com.intellij.openapi.roots.impl;
 
 import com.intellij.ProjectTopics;
+import com.intellij.openapi.Disposable;
 import com.intellij.openapi.application.ApplicationAdapter;
 import com.intellij.openapi.application.ApplicationManager;
 import com.intellij.openapi.components.ProjectComponent;
@@ -62,7 +63,7 @@ import java.util.Set;
 /**
  * ProjectRootManager extended with ability to watch events.
  */
-public class ProjectRootManagerComponent extends ProjectRootManagerImpl implements ProjectComponent {
+public class ProjectRootManagerComponent extends ProjectRootManagerImpl implements ProjectComponent, Disposable {
   private static final Logger LOG = Logger.getInstance(ProjectRootManagerComponent.class);
 
   private boolean myPointerChangesDetected = false;
@@ -307,6 +308,11 @@ public class ProjectRootManagerComponent extends ProjectRootManagerImpl implemen
     }
   }
 
+  @Override
+  public void dispose() {
+    assertListenersAreDisposed();
+  }
+
   private class AppListener extends ApplicationAdapter {
     @Override
     public void beforeWriteActionStart(@NotNull Object action) {

platform/projectModel-impl/src/com/intellij/openapi/roots/impl/ProjectRootManagerImpl.java

@@ -629,6 +629,22 @@ public class ProjectRootManagerImpl extends ProjectRootManagerEx implements Pers
     myJdkTableMultiListener.removeListener(jdkTableListener);
   }
 
+  protected void assertListenersAreDisposed() {
+    if (!myRegisteredRootProviders.isEmpty()) {
+      StringBuilder details = new StringBuilder();
+      for (Map.Entry<RootProvider, Set<OrderEntry>> entry : myRegisteredRootProviders.entrySet()) {
+        details.append(" ").append(entry.getKey()).append(" referenced by ").append(entry.getValue().size()).append(" order entries:\n");
+        for (OrderEntry orderEntry : entry.getValue()) {
+          details.append("   ").append(orderEntry).append("\n");
+        }
+      }
+      LOG.error("Listeners for " + myRegisteredRootProviders.size() + " root providers aren't disposed:" + details);
+      for (RootProvider provider : myRegisteredRootProviders.keySet()) {
+        provider.removeRootSetChangedListener(myRootProviderChangeListener);
+      }
+    }
+  }
+
   private class RootProviderChangeListener implements RootProvider.RootSetChangedListener {
     private boolean myInsideRootsChange;