Aperture: Update gallery placeholder background & drawable

Change-Id: I81622b26efea83e303bd73bcf43906a0632f5c41
diff --git a/app/src/main/res/drawable/ic_image.xml b/app/src/main/res/drawable/ic_image.xml
index 02e9b47..c7f7e0f 100644
--- a/app/src/main/res/drawable/ic_image.xml
+++ b/app/src/main/res/drawable/ic_image.xml
@@ -1,7 +1,6 @@
 <vector xmlns:android="http://schemas.android.com/apk/res/android"
     android:width="24dp"
     android:height="24dp"
-    android:tint="#000000"
     android:viewportWidth="24"
     android:viewportHeight="24">
     <path
diff --git a/app/src/main/res/drawable/ic_lock.xml b/app/src/main/res/drawable/ic_lock.xml
index 32ddf41..e24d946 100644
--- a/app/src/main/res/drawable/ic_lock.xml
+++ b/app/src/main/res/drawable/ic_lock.xml
@@ -1,7 +1,6 @@
 <vector xmlns:android="http://schemas.android.com/apk/res/android"
     android:width="24dp"
     android:height="24dp"
-    android:tint="#000000"
     android:viewportWidth="24"
     android:viewportHeight="24">
     <path
diff --git a/app/src/main/res/layout/activity_main.xml b/app/src/main/res/layout/activity_main.xml
index 14b5408..aab072c 100644
--- a/app/src/main/res/layout/activity_main.xml
+++ b/app/src/main/res/layout/activity_main.xml
@@ -221,7 +221,7 @@
             android:layout_height="60dp"
             android:layout_gravity="center"
             android:layout_marginStart="32dp"
-            android:background="?attr/selectableItemBackgroundBorderless"
+            android:backgroundTint="?colorSecondaryContainer"
             android:scaleType="fitXY"
             app:cardCornerRadius="8dp"
             app:layout_constraintBottom_toBottomOf="parent"