Improve window manager debug output.

Cleaned this up while I was debugging another issue.

Change-Id: I0663b9ed581c6868b59655a0f994d870971ec1a6
diff --git a/core/java/android/view/WindowManager.java b/core/java/android/view/WindowManager.java
index ff378a6..6b09049 100644
--- a/core/java/android/view/WindowManager.java
+++ b/core/java/android/view/WindowManager.java
@@ -1336,8 +1336,10 @@
             sb.append(type);
             sb.append(" fl=#");
             sb.append(Integer.toHexString(flags));
-            sb.append(" fmt=");
-            sb.append(format);
+            if (format != PixelFormat.OPAQUE) {
+                sb.append(" fmt=");
+                sb.append(format);
+            }
             if (windowAnimations != 0) {
                 sb.append(" wanim=0x");
                 sb.append(Integer.toHexString(windowAnimations));
@@ -1373,7 +1375,9 @@
                 sb.append(" sysuil=");
                 sb.append(hasSystemUiListeners);
             }
-            sb.append(" if=0x").append(Integer.toHexString(inputFeatures));
+            if (inputFeatures != 0) {
+                sb.append(" if=0x").append(Integer.toHexString(inputFeatures));
+            }
             sb.append('}');
             return sb.toString();
         }