upload android base code part4

android/compatibility/cdd/7_hardware-compatibility/7_0_intro.md

@@ -0,0 +1,32 @@
+# 7\. Hardware Compatibility
+
+If a device includes a particular hardware component that has a corresponding
+API for third-party developers:
+
+*    [C-0-1] The device implementation MUST implement that
+API as described in the Android SDK documentation.
+
+If an API in the SDK
+interacts with a hardware component that is stated to be optional and the
+device implementation does not possess that component:
+
+*   [C-0-2] Complete class definitions (as documented by the SDK) for the component
+APIs MUST still be presented.
+*   [C-0-3] The API’s behaviors MUST be implemented as no-ops in some reasonable
+fashion.
+*   [C-0-4] API methods MUST return null values where permitted by the SDK
+documentation.
+*   [C-0-5] API methods MUST return no-op implementations of classes where null values
+are not permitted by the SDK documentation.
+*   [C-0-6] API methods MUST NOT throw exceptions not documented by the SDK
+documentation.
+*    [C-0-7] Device implementations MUST consistently report accurate hardware
+configuration information via the `getSystemAvailableFeatures()` and
+`hasSystemFeature(String)` methods on the
+[android.content.pm.PackageManager](
+http://developer.android.com/reference/android/content/pm/PackageManager.html)
+class for the same build fingerprint.
+
+A typical example of a scenario where these requirements apply is the telephony
+API: Even on non-phone devices, these APIs must be implemented as reasonable
+no-ops.