Issue 61: Provide an extension point to have custom local file -> script mapping

plugins/org.chromium.debug.core/src/org/chromium/debug/core/SourceNameMapperContainer.java

Index: plugins/org.chromium.debug.core/src/org/chromium/debug/core/SourceNameMapperContainer.java
diff --git a/plugins/org.chromium.debug.core/src/org/chromium/debug/core/SourceNameMapperContainer.java b/plugins/org.chromium.debug.core/src/org/chromium/debug/core/SourceNameMapperContainer.java
index 5f38b2f844676945d28ce9478f88d2448d908bd7..8ee91723cb948fa09b95b59f48a97613b04c017e 100644
--- a/plugins/org.chromium.debug.core/src/org/chromium/debug/core/SourceNameMapperContainer.java
+++ b/plugins/org.chromium.debug.core/src/org/chromium/debug/core/SourceNameMapperContainer.java
@@ -1,5 +1,7 @@
 package org.chromium.debug.core;
 
+import org.chromium.debug.core.ReverseSourceLookup.ContainerWrapper;
+import org.eclipse.core.resources.IFile;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.Status;
@@ -18,7 +20,7 @@ import org.eclipse.osgi.util.NLS;
  * Currently container supports only prefix-based translation: if source name starts with a prefix,
  * the prefix is truncated; otherwise the source name is discarded.
  */
-public class SourceNameMapperContainer implements ISourceContainer {
+public class SourceNameMapperContainer implements ReverseLookupContainer {
 
   private static final String TYPE_ID =
       "org.chromium.debug.core.SourceNameMapperContainer.type"; //$NON-NLS-1$
@@ -74,6 +76,25 @@ public class SourceNameMapperContainer implements ISourceContainer {
     return true;
   }
 
+  @Override
+  public ContainerWrapper getReveseLookupImpl() {
+    final ContainerWrapper targetContainerWrapper =
+        ReverseSourceLookup.wrapSourceContainer(getTargetContainer());
+    if (targetContainerWrapper == null) {
+      return null;
+    }
+    return new ContainerWrapper() {
+      @Override
+      public String lookup(IFile resource) {
+        String subResult = targetContainerWrapper.lookup(resource);
+        if (subResult == null) {
+          return null;
+        }
+        return prefix + subResult;
+      }
+    };
+  }
+
   private String getMemento() throws CoreException {
     StringBuilder builder = new StringBuilder();
     MementoFormat.encodeComponent(prefix, builder);