Remove an updated dictionary that changed locales

When a dictionary changes locale, we need to remove the file
that corresponds to the old version. It has a different path
than the new one, so we have to search for it explicitly.

Bug: 6540631
Change-Id: Ie9d63ba636651fe90f8fbb9627b7265ac7b34ccd

java/src/com/android/inputmethod/latin/BinaryDictionaryFileDumper.java

@@ -193,6 +193,7 @@ public class BinaryDictionaryFileDumper {
                 if (0 >= resolver.delete(wordListUri, null, null)) {
                     Log.e(TAG, "Could not have the dictionary pack delete a word list");
                 }
+                BinaryDictionaryGetter.removeFilesWithIdExcept(context, id, outputFile);
                 // Success! Close files (through the finally{} clause) and return.
                 return AssetFileAddress.makeFromFileName(outputFileName);
             } catch (Exception e) {

java/src/com/android/inputmethod/latin/BinaryDictionaryGetter.java

@@ -282,6 +282,39 @@ class BinaryDictionaryGetter {
         return result;
     }
 
+    /**
+     * Remove all files with the passed id, except the passed file.
+     *
+     * If a dictionary with a given ID has a metadata change that causes it to change
+     * path, we need to remove the old version. The only way to do this is to check all
+     * installed files for a matching ID in a different directory.
+     */
+    public static void removeFilesWithIdExcept(final Context context, final String id,
+            final File fileToKeep) {
+        try {
+            final File canonicalFileToKeep = fileToKeep.getCanonicalFile();
+            final File[] directoryList = getCachedDirectoryList(context);
+            if (null == directoryList) return;
+            for (File directory : directoryList) {
+                // There is one directory per locale. See #getCachedDirectoryList
+                if (!directory.isDirectory()) continue;
+                final File[] wordLists = directory.listFiles();
+                if (null == wordLists) continue;
+                for (File wordList : wordLists) {
+                    final String fileId = getWordListIdFromFileName(wordList.getName());
+                    if (fileId.equals(id)) {
+                        if (!canonicalFileToKeep.equals(wordList.getCanonicalFile())) {
+                            wordList.delete();
+                        }
+                    }
+                }
+            }
+        } catch (java.io.IOException e) {
+            Log.e(TAG, "IOException trying to cleanup files : " + e);
+        }
+    }
+
+
     /**
      * Returns the id associated with the main word list for a specified locale.
      *