Fix errors when compiling with -Wall -Werror on Android.

This CL also turns those features on by default on Android

Review URL: https://codereview.appspot.com/7313049

git-svn-id: http://skia.googlecode.com/svn/trunk@7645 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/tests/PaintTest.cpp b/tests/PaintTest.cpp
index 2a84e4c..ed79076 100644
--- a/tests/PaintTest.cpp
+++ b/tests/PaintTest.cpp
@@ -29,8 +29,8 @@
 
 #ifdef SK_BUILD_FOR_ANDROID
     // the copy constructor should preserve the Generation ID
-    int32_t paintGenID = paint.getGenerationID();
-    int32_t copiedPaintGenID = copiedPaint.getGenerationID();
+    uint32_t paintGenID = paint.getGenerationID();
+    uint32_t copiedPaintGenID = copiedPaint.getGenerationID();
     REPORTER_ASSERT(reporter, paintGenID == copiedPaintGenID);
     REPORTER_ASSERT(reporter, !memcmp(&paint, &copiedPaint, sizeof(paint)));
 #endif