CLI: fixed missing "runtime.platform.path"

This happens when the CLI is runned without the `--board` option.

Fix #6463

Author: cmaglie

app/src/processing/app/Base.java

@@ -261,6 +261,10 @@ public Base(String[] args) throws Exception {
     if (!isCommandLine()) {
       rebuildBoardsMenu();
       rebuildProgrammerMenu();
+    } else {
+      TargetBoard lastSelectedBoard = BaseNoGui.getTargetBoard();
+      if (lastSelectedBoard != null)
+        BaseNoGui.selectBoard(lastSelectedBoard);
     }
 
     // Setup board-dependent variables.

build/shared/revisions.txt

@@ -4,6 +4,7 @@ ARDUINO 1.8.4
 * IDE Toolbar can now go full width on 4K display.
 * Environment variable LIBRARY_INDEX_URL is now correctly parsed (LIBRARY_INDEX_URL_GZ can also be optinally specified). Thanks @xardael
 * Added per-board generic option in config file boards.txt for disabling control of dtr+rts. Thanks @d-a-v
+* CLI: fixed missing "runtime.platform.path" when running without the `--board` option
 
 [libraries]
 * Fixed wrong folder name for "Adafruit Circuit Playground" library, now it can be updated cleanly.