Exclude words ending in -ion from Swedish minimal and light stemmers.

lucene/analysis/common/src/java/org/apache/lucene/analysis/sv/SwedishLightStemmer.java

@@ -87,6 +87,9 @@ class SwedishLightStemmer {
             || endsWith(s, len, "te")
             || endsWith(s, len, "et"))) return len - 2;
 
+    if (len > 5 && endsWith(s, len, "ion"))
+      return len;
+
     if (len > 3)
       switch (s[len - 1]) {
         case 't':

lucene/analysis/common/src/java/org/apache/lucene/analysis/sv/SwedishMinimalStemmer.java

@@ -82,6 +82,9 @@ class SwedishMinimalStemmer {
             || endsWith(s, len, "or")
             || endsWith(s, len, "en"))) return len - 2;
 
+    if (len > 5 && endsWith(s, len, "ion"))
+      return len;
+
     if (len > 3)
       switch (s[len - 1]) {
         case 'a':

lucene/analysis/common/src/test/org/apache/lucene/analysis/sv/minimal.txt

@@ -81,3 +81,6 @@ tomter	tomt
 tomtar	tomt
 änderna	änd
 ändar	änd
+reaktion	reaktion
+kommunikation	kommunikation
+inflation	inflation