Add the language switcher to the packages and classes pages for the Android Platform. am: 775276b773 am: 1c64cfff16 am: 892c1db70e am: 42dbce7f8f

Original change: https://android-review.googlesource.com/c/platform/tools/doc_generation/+/1433212

Change-Id: Ia10c75f82d678ab0ab2875f83611fec4182734bb
diff --git a/switcher4.py b/switcher4.py
index 90abb60..7e06fac 100644
--- a/switcher4.py
+++ b/switcher4.py
@@ -49,6 +49,28 @@
   sys.exit()
 
 
+# This method inserts the language switcher into the two top-level Android
+# Platform pages: packages.html and classes.html
+# For both Java and Kotlin
+def insert_platform_summaries():
+  global stubs
+  global java_stubs, kotlin_stubs
+  global verbose, work, show_solo
+  global java_source_abs_path
+  global kotlin_source_abs_path
+
+  stubs = 0
+  java_stubs = 0
+  kotlin_stubs = 0
+
+  java_source_abs_path = java_ref_root
+  kotlin_source_abs_path = kotlin_ref_root
+  insert_stub(os.path.join(java_ref_root, "packages.html"), True, True)
+  insert_stub(os.path.join(kotlin_ref_root, "packages.html"), False, True)
+
+  insert_stub(os.path.join(java_ref_root, "classes.html"), True, True)
+  insert_stub(os.path.join(kotlin_ref_root, "classes.html"), False, True)
+
 # This method uses switcher2, which assumes the refdocs stay in their current
 # assymetrical dirs (ref/android and ref/kotlin/android)
 # And just puts the switcher in the existing docs
@@ -247,6 +269,9 @@
       print "*** PLATFORM PAGES ***"
       print "======================"
 
+      # Insert the switchers at the top level first
+      insert_platform_summaries()
+
     elif source == "androidx":
       stem = "androidx"
       print