Fix crash with non-zero blurRadius less than 1

Summary:
There's a crash-inducing bug with `Image.blurRadius` on Android.

`blurRadius` is specified in JavaScript as a `float`, but it's cast to `int` before being passed to the `IterativeBoxBlurPostProcessor`. However, in `IterativeBoxBlurPostProcessor`, there is an argument precondition requiring the integer `blurRadius` to be non-zero.

Because the `== 0` condition is evaluated on the `float`, it's possible for a `blurRadius` in the range of `(0, 1)` (non-inclusive) to pass the conditional, and then be truncated to `0` and passed as an argument to `IterativeBoxBlurPostProcessor`, which will fail its precondition and crash the app.

This change works in our app, which was previously crashing.

[ANDROID] [BUGFIX] [Image] Fixed crash when specifying an Image.blurRadius between (0, 1)
Closes #16845

Differential Revision: D6387416

Pulled By: shergin

fbshipit-source-id: d5191aa97e949ffd41e6d68c96b3c7bcbc82a52e

ReactAndroid/src/main/java/com/facebook/react/views/image/ReactImageView.java

@@ -229,11 +229,11 @@ public void onFailure(String id, Throwable throwable) {
   }
 
   public void setBlurRadius(float blurRadius) {
-    if (blurRadius == 0) {
+    int pixelBlurRadius = (int) PixelUtil.toPixelFromDIP(blurRadius);
+    if (pixelBlurRadius == 0) {
       mIterativeBoxBlurPostProcessor = null;
     } else {
-      mIterativeBoxBlurPostProcessor =
-        new IterativeBoxBlurPostProcessor((int) PixelUtil.toPixelFromDIP(blurRadius));
+      mIterativeBoxBlurPostProcessor = new IterativeBoxBlurPostProcessor(pixelBlurRadius);
     }
     mIsDirty = true;
   }