Use -Werror in frameworks/native/opengl/tests

* Remove or comment out unused local variables.
* Remove unused function.
* Cast print argument type to fix format mismatch warning.

Bug: 66996870
Test: build with WITH_TIDY=1
Change-Id: I81e80849ac36288932df235cb0d63bd870357d86
diff --git a/opengl/tests/angeles/Android.bp b/opengl/tests/angeles/Android.bp
index bbbc447..5c398a6 100644
--- a/opengl/tests/angeles/Android.bp
+++ b/opengl/tests/angeles/Android.bp
@@ -8,6 +8,11 @@
         "demo.c",
     ],
 
+    cflags: [
+        "-Wall",
+        "-Werror",
+    ],
+
     gtest: false,
 
     shared_libs: [
diff --git a/opengl/tests/angeles/app-linux.cpp b/opengl/tests/angeles/app-linux.cpp
index ced8786..9d2c98f 100644
--- a/opengl/tests/angeles/app-linux.cpp
+++ b/opengl/tests/angeles/app-linux.cpp
@@ -62,9 +62,6 @@
 
 int gAppAlive = 1;
 
-static const char sAppName[] =
-        "San Angeles Observation OpenGL ES version example (Linux)";
-
 static int sWindowWidth = WINDOW_DEFAULT_WIDTH;
 static int sWindowHeight = WINDOW_DEFAULT_HEIGHT;
 static EGLDisplay sEglDisplay = EGL_NO_DISPLAY;
@@ -132,7 +129,6 @@
     EGLContext context;
     EGLConfig config;
     EGLSurface surface;
-    EGLint w, h;
     EGLDisplay dpy;
 
     EGLNativeWindowType window = windowSurface.getSurface();