Add explicit integer casts

WebKit uses the -Wshorten-64-to-32 flag which warns on these cases.

Bug: 3439
Change-Id: I8c1de60da0f173ca2036e2120e79b857f5f2775f
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1740866
Commit-Queue: James Darpinian <jdarpinian@chromium.org>
Reviewed-by: Kenneth Russell <kbr@chromium.org>

util/android/AndroidWindow.cpp

@@ -25,7 +25,7 @@ AndroidWindow::AndroidWindow() {}
 
 AndroidWindow::~AndroidWindow() {}
 
-bool AndroidWindow::initialize(const std::string &name, size_t width, size_t height)
+bool AndroidWindow::initialize(const std::string &name, int width, int height)
 {
     return resize(width, height);
 }