audio policy: fix crash in findPreferredDevice() on duplicating outputs

Duplicating outputs do not have an associated IOProfile and
getPolicyAudioPort() returns null.

Add a method to AudioIODescriptorInterface to query if the
input or output descriptor corresponds to MMAP IO profile or not.

Bug: 153849965
Test: repro steps in the bug
Change-Id: I300356880198f1785e3a5e1359ffd393c6ae4190

services/audiopolicy/common/managerdefinitions/include/AudioIODescriptorInterface.h

@@ -34,6 +34,8 @@ public:
     virtual audio_patch_handle_t getPatchHandle() const = 0;
 
     virtual void setPatchHandle(audio_patch_handle_t handle) = 0;
+
+    virtual bool isMmap() = 0;
 };
 
 template <class IoDescriptor, class Filter>
@@ -48,7 +50,7 @@ sp<DeviceDescriptor> findPreferredDevice(
         // created when the mmap stream is opened). This client is never active.
         // On non MMAP IOs, the preferred device is honored only if all active clients have
         // a preferred device in which case the first client drives the selection.
-        if (desc->getPolicyAudioPort()->isMmap()) {
+        if (desc->isMmap()) {
             // The client list is never empty on a MMAP IO
             return devices.getDeviceFromId(
                     desc->clientsList(false /*activeOnly*/)[0]->preferredDeviceId());

services/audiopolicy/common/managerdefinitions/include/AudioInputDescriptor.h

@@ -92,6 +92,12 @@ public:
     audio_config_base_t getConfig() const override;
     audio_patch_handle_t getPatchHandle() const override;
     void setPatchHandle(audio_patch_handle_t handle) override;
+    bool isMmap() override {
+        if (getPolicyAudioPort() != nullptr) {
+            return getPolicyAudioPort()->isMmap();
+        }
+        return false;
+    }
 
     status_t open(const audio_config_t *config,
                   const sp<DeviceDescriptor> &device,

services/audiopolicy/common/managerdefinitions/include/AudioOutputDescriptor.h

@@ -268,6 +268,12 @@ public:
     audio_config_base_t getConfig() const override;
     audio_patch_handle_t getPatchHandle() const override;
     void setPatchHandle(audio_patch_handle_t handle) override;
+    bool isMmap() override {
+        if (getPolicyAudioPort() != nullptr) {
+            return getPolicyAudioPort()->isMmap();
+        }
+        return false;
+    }
 
     TrackClientVector clientsList(bool activeOnly = false,
                                   product_strategy_t strategy = PRODUCT_STRATEGY_NONE,