Suppress / fix error prone warnings

Deal with the new set of warnings introduced by new error prone
version.

Test: `make` doesn't spit out warning messages anymore
Change-Id: I1eee8e5f89f3726e9b66f0bd3fe86154ebb4b79a

library/main/src/com/android/setupwizardlib/TemplateLayout.java

@@ -103,6 +103,8 @@ public class TemplateLayout extends FrameLayout {
      * by this view but not currently added to the view hierarchy. e.g. recycler view or list view
      * headers that are not currently shown.
      */
+    // Returning generic type is the common pattern used for findViewBy* methods
+    @SuppressWarnings("TypeParameterUnusedInFormals")
     public <T extends View> T findManagedViewById(int id) {
         return findViewById(id);
     }

library/main/src/com/android/setupwizardlib/view/Illustration.java

@@ -137,7 +137,8 @@ public class Illustration extends FrameLayout {
         if (mAspectRatio != 0.0f) {
             int parentWidth = MeasureSpec.getSize(widthMeasureSpec);
             int illustrationHeight = (int) (parentWidth / mAspectRatio);
-            illustrationHeight -= illustrationHeight % mBaselineGridSize;
+            illustrationHeight =
+                    (int) (illustrationHeight - (illustrationHeight % mBaselineGridSize));
             setPadding(0, illustrationHeight, 0, 0);
         }
         if (VERSION.SDK_INT >= VERSION_CODES.LOLLIPOP) {

library/recyclerview/src/com/android/setupwizardlib/GlifRecyclerLayout.java

@@ -107,6 +107,8 @@ public class GlifRecyclerLayout extends GlifLayout {
     }
 
     @Override
+    // Returning generic type is the common pattern used for findViewBy* methods
+    @SuppressWarnings("TypeParameterUnusedInFormals")
     public <T extends View> T findManagedViewById(int id) {
         final View header = mRecyclerMixin.getHeader();
         if (header != null) {

library/recyclerview/src/com/android/setupwizardlib/SetupWizardRecyclerLayout.java

@@ -127,6 +127,8 @@ public class SetupWizardRecyclerLayout extends SetupWizardLayout {
     }
 
     @Override
+    // Returning generic type is the common pattern used for findViewBy* methods
+    @SuppressWarnings("TypeParameterUnusedInFormals")
     public <T extends View> T findManagedViewById(int id) {
         final View header = mRecyclerMixin.getHeader();
         if (header != null) {