Aperture: Redo bottom section paddings

* Set proper padding for mode selection layout so it looks good on
devices with hardware navigation keys
* Don't center gallery and flip camera buttons, constrain them to the
external walls

Change-Id: I3102d13f5d7e2e52fd05b8e599317a873c52e340
diff --git a/app/src/main/res/drawable/flip_camera_button_background.xml b/app/src/main/res/drawable/flip_camera_button_background.xml
index 16e4b03..45db6d0 100644
--- a/app/src/main/res/drawable/flip_camera_button_background.xml
+++ b/app/src/main/res/drawable/flip_camera_button_background.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <shape xmlns:android="http://schemas.android.com/apk/res/android">
     <solid android:color="?attr/colorPrimary" />
-    <corners android:radius="25dp" />
+    <corners android:radius="30dp" />
     <padding
         android:bottom="7dp"
         android:left="7dp"
diff --git a/app/src/main/res/layout/activity_main.xml b/app/src/main/res/layout/activity_main.xml
index 0340d91..8bce6b9 100644
--- a/app/src/main/res/layout/activity_main.xml
+++ b/app/src/main/res/layout/activity_main.xml
@@ -195,7 +195,8 @@
     <androidx.constraintlayout.widget.ConstraintLayout
         android:id="@+id/bottomButtonsLayout"
         android:layout_width="0dp"
-        android:layout_height="120dp"
+        android:layout_height="wrap_content"
+        android:paddingTop="8dp"
         app:layout_constraintBottom_toTopOf="@+id/mode_selector_layout"
         app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintStart_toStartOf="parent">
@@ -219,11 +220,11 @@
             android:layout_width="60dp"
             android:layout_height="60dp"
             android:layout_gravity="center"
+            android:layout_marginStart="32dp"
             android:background="?attr/selectableItemBackgroundBorderless"
             android:scaleType="fitXY"
             app:cardCornerRadius="8dp"
             app:layout_constraintBottom_toBottomOf="parent"
-            app:layout_constraintEnd_toStartOf="@+id/shutterButton"
             app:layout_constraintStart_toStartOf="parent"
             app:layout_constraintTop_toTopOf="parent">
 
@@ -238,24 +239,22 @@
         <ImageButton
             android:id="@+id/flipCameraButton"
             style="@style/ApertureFlipCameraButton"
-            android:layout_width="50dp"
-            android:layout_height="50dp"
+            android:layout_width="60dp"
+            android:layout_height="60dp"
+            android:layout_marginEnd="32dp"
             android:contentDescription="@string/flip_camera_button_description"
             android:scaleType="center"
             android:src="@drawable/ic_flip_camera_anim"
             app:layout_constraintBottom_toBottomOf="parent"
             app:layout_constraintEnd_toEndOf="parent"
-            app:layout_constraintStart_toEndOf="@+id/shutterButton"
             app:layout_constraintTop_toTopOf="parent" />
     </androidx.constraintlayout.widget.ConstraintLayout>
 
     <androidx.constraintlayout.widget.ConstraintLayout
         android:id="@+id/mode_selector_layout"
         android:layout_width="match_parent"
-        android:layout_height="50dp"
-        android:layout_marginStart="6dp"
-        android:layout_marginEnd="6dp"
-        android:layout_marginBottom="12dp"
+        android:layout_height="0dp"
+        android:padding="16dp"
         app:layout_constraintBottom_toBottomOf="parent"
         app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintStart_toStartOf="parent">