remove kA1_Config, as it is no longer supported

src/animator/SkDrawBitmap.cpp

Index: src/animator/SkDrawBitmap.cpp
diff --git a/src/animator/SkDrawBitmap.cpp b/src/animator/SkDrawBitmap.cpp
index 568401d0e667cfe3ed63f4269a8361e24d99f848..327e81365af40e2800646a0c07024a5b8699613c 100644
--- a/src/animator/SkDrawBitmap.cpp
+++ b/src/animator/SkDrawBitmap.cpp
@@ -75,11 +75,10 @@ void SkDrawBitmap::dump(SkAnimateMaker* maker) {
     const char* formatName;
     switch (format) {
         case 0: formatName = "none"; break;
-        case 1: formatName = "A1"; break;
-        case 2: formatName = "A8"; break;
-        case 3: formatName = "Index8"; break;
-        case 4: formatName = "RGB16"; break;
-        case 5: formatName = "RGB32"; break;
+        case 1: formatName = "A8"; break;
+        case 2: formatName = "Index8"; break;
+        case 3: formatName = "RGB16"; break;
+        case 4: formatName = "RGB32"; break;
     }
     SkDebugf("format=\"%s\" />\n", formatName);
 }