coverity#1339308 Uncaught exception

Change-Id: Id63bbdd11af66de6be8a3e9dfca1c7efbe74b08a

l10ntools/inc/po.hxx

@@ -123,7 +123,7 @@ private:
 
 public:
 
-    enum Exception { INVALIDENTRY };
+    class Exception : public std::exception { };
 
             PoIfstream();
             PoIfstream( const OString& rFileName );

l10ntools/source/merge.cxx

@@ -45,15 +45,12 @@ namespace
         {
             rPoFile.readEntry( o_rPoEntry );
         }
-        catch( PoIfstream::Exception& aException )
+        catch (const PoIfstream::Exception&)
         {
-            if( aException == PoIfstream::INVALIDENTRY )
-            {
-                printf(
-                    "Warning : %s contains invalid entry\n",
-                    rFileName.getStr() );
-                return false;
-            }
+            printf(
+                "Warning : %s contains invalid entry\n",
+                rFileName.getStr() );
+            return false;
         }
         return true;
     }

l10ntools/source/po.cxx

@@ -596,7 +596,7 @@ void PoIfstream::readEntry( PoEntry& rPoEntry )
         }
         else
         {
-            throw INVALIDENTRY;
+            throw PoIfstream::Exception();
         }
     }
 }