Revert "Do not decrease compose hint font size"

This reverts commit bf806bd717.

Fixes #5297
// FREEBIE

src/org/thoughtcrime/securesms/components/ComposeText.java

@@ -5,9 +5,12 @@ import android.content.res.Configuration;
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.text.InputType;
+import android.text.Spannable;
+import android.text.SpannableString;
 import android.text.SpannableStringBuilder;
 import android.text.TextUtils;
 import android.text.TextUtils.TruncateAt;
+import android.text.style.RelativeSizeSpan;
 import android.util.AttributeSet;
 import android.view.inputmethod.EditorInfo;
 
@@ -18,8 +21,8 @@ import org.thoughtcrime.securesms.util.TextSecurePreferences;
 
 public class ComposeText extends EmojiEditText {
 
-  private CharSequence hint;
-  private CharSequence subHint;
+  private SpannableString hint;
+  private SpannableString subHint;
 
   public ComposeText(Context context) {
     super(context);
@@ -56,8 +59,15 @@ public class ComposeText extends EmojiEditText {
   }
 
   public void setHint(@NonNull String hint, @Nullable CharSequence subHint) {
-    this.hint = hint;
-    this.subHint = subHint;
+    this.hint = new SpannableString(hint);
+    this.hint.setSpan(new RelativeSizeSpan(0.8f), 0, hint.length(), Spannable.SPAN_INCLUSIVE_INCLUSIVE);
+
+    if (subHint != null) {
+      this.subHint = new SpannableString(subHint);
+      this.subHint.setSpan(new RelativeSizeSpan(0.8f), 0, subHint.length(), Spannable.SPAN_INCLUSIVE_INCLUSIVE);
+    } else {
+      this.subHint = null;
+    }
 
     if (this.subHint != null) {
       super.setHint(new SpannableStringBuilder().append(ellipsizeToWidth(this.hint))