Resolve embedded text vars

Title Block text variables are embedded into the pcb file and should
be used for resolving when the project file is missing

common/title_block.cpp

@@ -95,6 +95,7 @@ void TITLE_BLOCK::GetContextualTextVars( wxArrayString* aVars )
 bool TITLE_BLOCK::TextVarResolver( wxString* aToken, const PROJECT* aProject ) const
 {
     bool tokenUpdated = false;
+    wxString originalToken = *aToken;
 
     if( aToken->IsSameAs( wxT( "ISSUE_DATE" ) ) )
     {
@@ -150,7 +151,12 @@ bool TITLE_BLOCK::TextVarResolver( wxString* aToken, const PROJECT* aProject ) c
 
     if( tokenUpdated )
     {
-       *aToken = ExpandTextVars( *aToken, aProject );
+        *aToken = ExpandTextVars( *aToken, aProject );
+
+        // This is the default fallback, so don't claim we resolved it
+        if( *aToken == wxT( "${" ) + originalToken + wxT( "}" ) )
+            return false;
+
        return true;
     }
 

pcbnew/board.cpp

@@ -298,13 +298,15 @@ std::vector<PCB_MARKER*> BOARD::ResolveDRCExclusions()
 
 bool BOARD::ResolveTextVar( wxString* token, int aDepth ) const
 {
+    wxString var = *token;
+
     if( GetTitleBlock().TextVarResolver( token, m_project ) )
     {
         return true;
     }
-    else if( m_properties.count( *token ) )
+    else if( m_properties.count( var ) )
     {
-        *token = m_properties.at( *token );
+        *token = m_properties.at( var );
         return true;
     }