[290581] Manual validation is cleaning up the already validated cache on every call
diff --git a/plugins/org.eclipse.wst.validation/validate_core/org/eclipse/wst/validation/internal/provisional/core/IValidatorExtender.java b/plugins/org.eclipse.wst.validation/validate_core/org/eclipse/wst/validation/internal/provisional/core/IValidatorExtender.java
new file mode 100644
index 0000000..581a6b0
--- /dev/null
+++ b/plugins/org.eclipse.wst.validation/validate_core/org/eclipse/wst/validation/internal/provisional/core/IValidatorExtender.java
@@ -0,0 +1,11 @@
+package org.eclipse.wst.validation.internal.provisional.core;
+
+import org.eclipse.core.resources.IProject;
+import org.eclipse.core.runtime.IProgressMonitor;
+import org.eclipse.wst.validation.ValidationState;
+
+public interface IValidatorExtender {
+
+	void validationFinishing(IProject project, ValidationState state, IProgressMonitor monitor);
+
+}
diff --git a/plugins/org.eclipse.wst.validation/vf2/org/eclipse/wst/validation/Validator.java b/plugins/org.eclipse.wst.validation/vf2/org/eclipse/wst/validation/Validator.java
index 69bb883..7a9da1c 100644
--- a/plugins/org.eclipse.wst.validation/vf2/org/eclipse/wst/validation/Validator.java
+++ b/plugins/org.eclipse.wst.validation/vf2/org/eclipse/wst/validation/Validator.java
@@ -57,6 +57,7 @@
 import org.eclipse.wst.validation.internal.plugin.ValidationPlugin;
 import org.eclipse.wst.validation.internal.provisional.core.IMessage;
 import org.eclipse.wst.validation.internal.provisional.core.IValidator;
+import org.eclipse.wst.validation.internal.provisional.core.IValidatorExtender;
 
 /**
  * Represents a validator. This gets instantiated through one of the validator extension points.
@@ -651,6 +652,17 @@
 	}
 	
 	@Override
+	public void validationFinishing(IProject project, ValidationState state, IProgressMonitor monitor) {
+		if (project != null) {
+			IValidator v = asIValidator();
+			if (v instanceof IValidatorExtender) {
+				IValidatorExtender vExt = (IValidatorExtender) v;
+				vExt.validationFinishing(project, state, monitor);
+			}	
+		}
+	}
+
+	@Override
 	public IValidator asIValidator() {
 		IValidator v = null;
 		try {