Display a generated avatar icon rather than a single default.

If the contact doesn't have an image, render a color-coded
background and the first letter of the contact's name.

1) Don't display anything during recipient resolution.

2) Display a # icon in material gray for recipients with no name.

3) Display a material group icon in material gray for groups with
   no avatar icon set.

Closes #3104

// FREEBIE

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

@@ -0,0 +1,49 @@
+package org.thoughtcrime.securesms.components;
+
+import android.content.Context;
+import android.content.Intent;
+import android.provider.ContactsContract;
+import android.util.AttributeSet;
+import android.view.View;
+import android.widget.ImageView;
+
+import org.thoughtcrime.securesms.recipients.Recipient;
+
+public class AvatarImageView extends ImageView {
+
+  public AvatarImageView(Context context) {
+    super(context);
+    setScaleType(ScaleType.CENTER_INSIDE);
+  }
+
+  public AvatarImageView(Context context, AttributeSet attrs) {
+    super(context, attrs);
+    setScaleType(ScaleType.CENTER_INSIDE);
+  }
+
+  public void setAvatar(Recipient recipient, boolean quickContactEnabled) {
+    setImageDrawable(recipient.getContactPhoto());
+    setAvatarClickHandler(recipient, quickContactEnabled);
+  }
+
+  private void setAvatarClickHandler(final Recipient recipient, boolean quickContactEnabled) {
+    if (!recipient.isGroupRecipient() && quickContactEnabled) {
+      setOnClickListener(new View.OnClickListener() {
+        @Override
+        public void onClick(View v) {
+          if (recipient.getContactUri() != null) {
+            ContactsContract.QuickContact.showQuickContact(getContext(), AvatarImageView.this, recipient.getContactUri(), ContactsContract.QuickContact.MODE_LARGE, null);
+          } else {
+            final Intent intent = new Intent(Intent.ACTION_INSERT_OR_EDIT);
+            intent.putExtra(ContactsContract.Intents.Insert.PHONE, recipient.getNumber());
+            intent.setType(ContactsContract.Contacts.CONTENT_ITEM_TYPE);
+            getContext().startActivity(intent);
+          }
+        }
+      });
+    } else {
+      setOnClickListener(null);
+    }
+  }
+
+}