Creating new gn arg: enable_all_proguard_optimizations.

BUILD.gn

Index: BUILD.gn
diff --git a/BUILD.gn b/BUILD.gn
index 38e5b95047f8ff2c7abfc3c5bb81c927fe24d897..dd77e42d4091856f227f34e0d240d484287a8577 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -387,11 +387,13 @@ group("both_gn_and_gyp") {
         "//components/cronet/android:cronet_package",
         "//components/cronet/android:cronet_perf_test_apk",
         "//components/cronet/android:cronet_sample_apk",
-        "//components/cronet/android:cronet_sample_test_apk",
         "//components/cronet/android:cronet_test_apk",
         "//components/cronet/android:cronet_test_instrumentation_apk",
         "//components/cronet/android:cronet_unittests",
       ]
+      if (!enable_all_proguard_optimizations) {
+        deps += [ "//components/cronet/android:cronet_sample_test_apk" ]
+      }
     }
 
     if (!is_chromecast) {
@@ -402,12 +404,16 @@ group("both_gn_and_gyp") {
         "//android_webview/tools/system_webview_shell",
         "//chrome/android:chrome_junit_tests",
         "//chrome/android:chrome_public_apk",
-        "//chrome/android:chrome_public_test_apk",
-        "//chrome/android:chrome_sync_shell_test_apk",
         "//chrome/test/chromedriver/test/webview_shell:chromedriver_webview_shell_apk",
         "//content/shell/android:content_shell_test_apk",
         "//third_party/custom_tabs_client:custom_tabs_client_example_apk",
       ]
+      if (!enable_all_proguard_optimizations) {
+        deps += [
+          "//chrome/android:chrome_public_test_apk",
+          "//chrome/android:chrome_sync_shell_test_apk",
+        ]
+      }
     }
 
     if (target_cpu != "x64") {