Camera: Cache physical camera id values

A pointer to data within CameraMetadata can become
invalid after each metadata modification. Cache any
values that could potentially point to the raw
internal metadata buffer.

Bug: 123954417
Test: Camera CTS
Change-Id: Ie5ac9600ff454af551c4cf8e0f25ba5a6a6e897d

camera/ndk/impl/ACameraMetadata.cpp

@@ -104,7 +104,8 @@ ACameraMetadata::derivePhysicalCameraIds() {
     for (size_t i = 0; i < entry.count; ++i) {
         if (ids[i] == '\0') {
             if (start != i) {
-                mStaticPhysicalCameraIds.push_back((const char*)ids+start);
+                mStaticPhysicalCameraIdValues.push_back(String8((const char *)ids+start));
+                mStaticPhysicalCameraIds.push_back(mStaticPhysicalCameraIdValues.back().string());
             }
             start = i+1;
         }

camera/ndk/impl/ACameraMetadata.h

@@ -117,6 +117,7 @@ struct ACameraMetadata : public RefBase {
     static std::unordered_set<uint32_t> sSystemTags;
 
     std::vector<const char*> mStaticPhysicalCameraIds;
+    std::vector<String8> mStaticPhysicalCameraIdValues;
 };
 
 #endif // _ACAMERA_METADATA_H