Wait for next available frame

... for the maximal possible time not
violating the min fps.

Bug: 301023410
Test: atest VirtualCameraTest
Test: atest CtsVirtualDevicesCameraCtsTestCases

Change-Id: Iebc3eae22e54fc153a2daa19e7ea331d89b16a8e
diff --git a/services/camera/virtualcamera/VirtualCameraDevice.cc b/services/camera/virtualcamera/VirtualCameraDevice.cc
index fe9e0ed..ba4ea6b 100644
--- a/services/camera/virtualcamera/VirtualCameraDevice.cc
+++ b/services/camera/virtualcamera/VirtualCameraDevice.cc
@@ -73,13 +73,14 @@
 
 constexpr int32_t kMaxJpegSize = 3 * 1024 * 1024 /*3MiB*/;
 
-constexpr int32_t kMinFps = 15;
-
 constexpr std::chrono::nanoseconds kMaxFrameDuration =
-    std::chrono::duration_cast<std::chrono::nanoseconds>(1e9ns / kMinFps);
+    std::chrono::duration_cast<std::chrono::nanoseconds>(
+        1e9ns / VirtualCameraDevice::kMinFps);
 
 constexpr uint8_t kPipelineMaxDepth = 2;
 
+constexpr int k30Fps = 30;
+
 constexpr MetadataBuilder::ControlRegion kDefaultEmptyControlRegion{};
 
 const std::array<Resolution, 5> kStandardJpegThumbnailSizes{
@@ -130,16 +131,20 @@
   std::set<FpsRange> availableRanges;
 
   for (const SupportedStreamConfiguration& config : configs) {
-    availableRanges.insert({.minFps = kMinFps, .maxFps = config.maxFps});
+    availableRanges.insert(
+        {.minFps = VirtualCameraDevice::kMinFps, .maxFps = config.maxFps});
     availableRanges.insert({.minFps = config.maxFps, .maxFps = config.maxFps});
   }
 
   if (std::any_of(configs.begin(), configs.end(),
                   [](const SupportedStreamConfiguration& config) {
-                    return config.maxFps >= 30;
+                    return config.maxFps >= k30Fps;
                   })) {
-    availableRanges.insert({.minFps = kMinFps, .maxFps = 30});
-    availableRanges.insert({.minFps = 30, .maxFps = 30});
+    // Extend the set of available ranges with (minFps <= 15, 30) & (30, 30) as
+    // required by CDD.
+    availableRanges.insert(
+        {.minFps = VirtualCameraDevice::kMinFps, .maxFps = k30Fps});
+    availableRanges.insert({.minFps = k30Fps, .maxFps = k30Fps});
   }
 
   return std::vector<FpsRange>(availableRanges.begin(), availableRanges.end());