Android: Remove enable_chrome_language_splits GN arg

It's purpose was to turn on splits. Now that they have shipped, there's
no need to be able to turn them off.

Leaving reference int diagnose_bloat.py (at least for a while) since
that script needs to be able to sync back past this change.

Change-Id: I9a4cfae043497e811db9fc8509688b8adee0fed5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1617134
Auto-Submit: Andrew Grieve <agrieve@chromium.org>
Reviewed-by: Ben Mason <benmason@chromium.org>
Commit-Queue: Ben Mason <benmason@chromium.org>
Cr-Commit-Position: refs/heads/master@{#660932}

chrome/android/BUILD.gn

@@ -2116,7 +2116,7 @@ android_app_bundle("chrome_modern_public_bundle") {
   if (!is_java_debug) {
     proguard_enabled = true
   }
-  enable_language_splits = enable_chrome_language_splits
+  enable_language_splits = true
   compress_shared_libraries = true
   min_sdk_version = 21
   if (enable_vr) {
@@ -2272,7 +2272,7 @@ template("monochrome_or_trichrome_public_bundle_tmpl") {
         verify_proguard_flags = true
       }
     }
-    enable_language_splits = enable_chrome_language_splits
+    enable_language_splits = true
     min_sdk_version = _min_sdk_version
 
     if (trichrome_synchronized_proguard) {

chrome/android/chrome_public_apk_tmpl.gni

@@ -21,9 +21,6 @@ declare_args() {
   # Experimental only. Causes .dex files to be store in the APK uncompressed.
   # Only affects monochrome_public_apk and trichrome_chrome_apk.
   use_uncompressed_dex = false
-
-  # Enable language splits in the Chrome bundles.
-  enable_chrome_language_splits = true
 }
 
 default_chrome_public_jinja_variables = [