Extract broadcasting to a separate util function

So that it can be used in other operations.
Add new tests file for utility functions, a target to build it and a
test for the newly created broadcasting function.

Test: NeuralNetworkTest_static
Test: NeuralNetworkTest_utils
Change-Id: I5d4b84d078668d2d879bb032132641a36549f3dd
Merged-In: I5d4b84d078668d2d879bb032132641a36549f3dd
(cherry picked from commit f4cc13ed33f189c236e4565bcff72e755ccd12a0)

common/Android.bp

diff --git a/common/Android.bp b/common/Android.bp
index 2e353f3..f5c76e1 100644
--- a/common/Android.bp
+++ b/common/Android.bp
@@ -161,3 +161,33 @@
         "tensorflow_headers",
     ],
 }
+
+cc_test {
+    name: "NeuralNetworksTest_utils",
+    shared_libs: [
+        "libhidlmemory",
+        "libneuralnetworks",
+        "android.hardware.neuralnetworks@1.0",
+        "android.hardware.neuralnetworks@1.1",
+        "android.hardware.neuralnetworks@1.2",
+        "android.hidl.allocator@1.0",
+        "android.hidl.memory@1.0",
+    ],
+    static_libs: [
+        "libbase",
+        "libgmock",
+        "liblog",
+        "libneuralnetworks_common",
+    ],
+    cflags: [
+        "-Wno-extern-c-compat",
+        "-Wno-unused-variable",
+    ],
+    srcs: [
+        "UtilsTest.cpp",
+    ],
+    local_include_dirs: [ "include" ],
+    header_libs: [
+        "tensorflow_headers",
+    ],
+}