tests: Clean up some MSVC++ compiler warnings

Known issues running tests on Windows:

- Compiler warnings from gtest that we haven’t spent the time to figure out

- Tests don’t run in place - you need to have them in the same directory with vulkan.dll,
  gtest.dll, and if MSVC++ is not installed, the MSVC++ runtime dlls.  If you want to use
  the --compare-images option to vk_render_tests, you will need the “golden”
  folder with golden images.

- vk_layer_validation_tests will fail unless you specify VK_LAYER_NAMES as Validation
  in the registry or  environment. You will also need to specify VK_LAYERS_PATH to point
  to the layer dlls.   The mismatched type validation test will fail regardless as the
  check it is testing for did not make it into the SDK branch

- Known issue of parameter checker for CreateDepthStencilView expecting msaaResolveSubresource
  to be valid even if msaa isn’t active

- Problem with runtime assert or hang in shader tracker - for now just remove the
  shader checker files from your VK_LAYERS_PATH location.
diff --git a/tests/vktestframework.cpp b/tests/vktestframework.cpp
index 24b76a6..85e56fb 100644
--- a/tests/vktestframework.cpp
+++ b/tests/vktestframework.cpp
@@ -91,8 +91,8 @@
     bool                                    m_quit;
     bool                                    m_pause;
 
-    uint32_t                                m_width;
-    uint32_t                                m_height;
+    int                                     m_width;
+    int                                     m_height;
 
     std::list<VkTestImageRecord>::iterator m_display_image;
 
@@ -236,7 +236,7 @@
 {
     string filename;
     VkResult err;
-    int x, y;
+    uint32_t x, y;
     VkImageObj displayImage(image->device());
     VkMemoryPropertyFlags reqs = VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT;
 
@@ -319,14 +319,14 @@
     magick_wand_1=NewMagickWand();
     sprintf(testimage,"%s.ppm",basename);
     status=MagickReadImage(magick_wand_1,testimage);
-    ASSERT_TRUE(status) << "Unable to open file: " << testimage;
+    ASSERT_EQ(status, MagickTrue) << "Unable to open file: " << testimage;
 
 
     MagickWandGenesis();
     magick_wand_2=NewMagickWand();
     sprintf(golden,"%s/%s.ppm",golddir,basename);
     status=MagickReadImage(magick_wand_2,golden);
-    ASSERT_TRUE(status) << "Unable to open file: " << golden;
+    ASSERT_EQ(status, MagickTrue) << "Unable to open file: " << golden;
 
     compare_wand=MagickCompareImages(magick_wand_1,magick_wand_2, MeanAbsoluteErrorMetric, &differenz);
     if (differenz != 0.0)