build: add missing proguard rules

Change-Id: I6a35121d49efb4b695d3eb092b74bea041f1096a
diff --git a/ring-android/app/proguard-rules.pro b/ring-android/app/proguard-rules.pro
index ca2db8f..5d5fd8e 100644
--- a/ring-android/app/proguard-rules.pro
+++ b/ring-android/app/proguard-rules.pro
@@ -43,10 +43,14 @@
 # EZVcard
 -keep,includedescriptorclasses class ezvcard.** { *; }
 -keepclassmembers class ezvcard.** { *; }
+-keep,includedescriptorclasses class com.github.mangstadt.vinnie.** { *; }
+-keepclassmembers class com.github.mangstadt.vinnie.** { *; }
 
 # barcodescanner
 -keep,includedescriptorclasses class com.journeyapps.barcodescanner.** { *; }
 -keepclassmembers class com.journeyapps.barcodescanner.** { *; }
+-keep,includedescriptorclasses class com.google.zxing.** { *; }
+-keepclassmembers class com.google.zxing.** { *; }
 
 # stickylistheaders
 -keep,includedescriptorclasses class se.emilsjolander.stickylistheaders.** { *; }
@@ -70,4 +74,5 @@
 -keep public enum com.bumptech.glide.load.resource.bitmap.ImageHeaderParser$** {
   **[] $VALUES;
   public *;
-}
\ No newline at end of file
+}
+