Grab display information for render thread through java

With HWUI becoming an APEX module, we need to use public apis wherever
possible - since there aren't plans to expose a stable api for physical
display information through native, instead grab the system context
from ActivityThread so that we can use DisplayManager's public apis.

The api for retrieving the system context is left as a hidden api - a
future change should stabilize the API or switch to a new api that does
not yet exist. But, this is the right shape for plumbing through the
display information, as the old code retrieved it through SurfaceFlinger
which should not be stabilized as the source of truth for display
information is DisplayManagerService.

Bug: 146387012
Bug: 150880248
Test: builds, boots, verified that the correct display info is plumbed
down

Change-Id: I1a99a72244969bdece2903993e3beb27a6e534b1
diff --git a/libs/hwui/DeviceInfo.cpp b/libs/hwui/DeviceInfo.cpp
index 1c947a7..1a84313 100644
--- a/libs/hwui/DeviceInfo.cpp
+++ b/libs/hwui/DeviceInfo.cpp
@@ -15,6 +15,8 @@
  */
 
 #include <DeviceInfo.h>
+#include <android/hardware_buffer.h>
+#include <apex/display.h>
 #include <log/log.h>
 #include <utils/Errors.h>
 
@@ -30,14 +32,47 @@
 
 DeviceInfo::DeviceInfo() {
 #if HWUI_NULL_GPU
-        mMaxTextureSize = NULL_GPU_MAX_TEXTURE_SIZE;
+    mMaxTextureSize = NULL_GPU_MAX_TEXTURE_SIZE;
 #else
-        mMaxTextureSize = -1;
+    mMaxTextureSize = -1;
 #endif
-        updateDisplayInfo();
 }
-DeviceInfo::~DeviceInfo() {
-    ADisplay_release(mDisplays);
+
+void DeviceInfo::updateDisplayInfo() {
+    if (Properties::isolatedProcess) {
+        return;
+    }
+
+    ADisplay** displays;
+    int size = ADisplay_acquirePhysicalDisplays(&displays);
+
+    if (size <= 0) {
+        LOG_ALWAYS_FATAL("Failed to acquire physical displays for WCG support!");
+    }
+
+    for (int i = 0; i < size; ++i) {
+        // Pick the first internal display for querying the display type
+        // In practice this is controlled by a sysprop so it doesn't really
+        // matter which display we use.
+        if (ADisplay_getDisplayType(displays[i]) == DISPLAY_TYPE_INTERNAL) {
+            // We get the dataspace from DisplayManager already. Allocate space
+            // for the result here but we don't actually care about using it.
+            ADataSpace dataspace;
+            AHardwareBuffer_Format pixelFormat;
+            ADisplay_getPreferredWideColorFormat(displays[i], &dataspace, &pixelFormat);
+
+            if (pixelFormat == AHARDWAREBUFFER_FORMAT_R8G8B8A8_UNORM) {
+                mWideColorType = SkColorType::kN32_SkColorType;
+            } else if (pixelFormat == AHARDWAREBUFFER_FORMAT_R16G16B16A16_FLOAT) {
+                mWideColorType = SkColorType::kRGBA_F16_SkColorType;
+            } else {
+                LOG_ALWAYS_FATAL("Unreachable: unsupported pixel format: %d", pixelFormat);
+            }
+            ADisplay_release(displays);
+            return;
+        }
+    }
+    LOG_ALWAYS_FATAL("Failed to find a valid physical display for WCG support!");
 }
 
 int DeviceInfo::maxTextureSize() const {
@@ -49,73 +84,26 @@
     DeviceInfo::get()->mMaxTextureSize = maxTextureSize;
 }
 
-void DeviceInfo::onRefreshRateChanged(int64_t vsyncPeriod) {
-    mVsyncPeriod = vsyncPeriod;
+void DeviceInfo::setWideColorDataspace(ADataSpace dataspace) {
+    switch (dataspace) {
+        case ADATASPACE_DISPLAY_P3:
+            get()->mWideColorSpace =
+                    SkColorSpace::MakeRGB(SkNamedTransferFn::kSRGB, SkNamedGamut::kDCIP3);
+            break;
+        case ADATASPACE_SCRGB:
+            get()->mWideColorSpace = SkColorSpace::MakeSRGB();
+            break;
+        case ADATASPACE_SRGB:
+            // when sRGB is returned, it means wide color gamut is not supported.
+            get()->mWideColorSpace = SkColorSpace::MakeSRGB();
+            break;
+        default:
+            LOG_ALWAYS_FATAL("Unreachable: unsupported wide color space.");
+    }
 }
 
-void DeviceInfo::updateDisplayInfo() {
-    if (Properties::isolatedProcess) {
-        return;
-    }
-
-    if (mCurrentConfig == nullptr) {
-        mDisplaysSize = ADisplay_acquirePhysicalDisplays(&mDisplays);
-        LOG_ALWAYS_FATAL_IF(mDisplays == nullptr || mDisplaysSize <= 0,
-                            "Failed to get physical displays: no connected display: %d!", mDisplaysSize);
-        for (size_t i = 0; i < mDisplaysSize; i++) {
-            ADisplayType type = ADisplay_getDisplayType(mDisplays[i]);
-            if (type == ADisplayType::DISPLAY_TYPE_INTERNAL) {
-                mPhysicalDisplayIndex = i;
-                break;
-            }
-        }
-        LOG_ALWAYS_FATAL_IF(mPhysicalDisplayIndex < 0, "Failed to find a connected physical display!");
-
-
-        // Since we now just got the primary display for the first time, then
-        // store the primary display metadata here.
-        ADisplay* primaryDisplay = mDisplays[mPhysicalDisplayIndex];
-        mMaxRefreshRate = ADisplay_getMaxSupportedFps(primaryDisplay);
-        ADataSpace dataspace;
-        AHardwareBuffer_Format format;
-        ADisplay_getPreferredWideColorFormat(primaryDisplay, &dataspace, &format);
-        switch (dataspace) {
-            case ADATASPACE_DISPLAY_P3:
-                mWideColorSpace =
-                        SkColorSpace::MakeRGB(SkNamedTransferFn::kSRGB, SkNamedGamut::kDCIP3);
-                break;
-            case ADATASPACE_SCRGB:
-                mWideColorSpace = SkColorSpace::MakeSRGB();
-                break;
-            case ADATASPACE_SRGB:
-                // when sRGB is returned, it means wide color gamut is not supported.
-                mWideColorSpace = SkColorSpace::MakeSRGB();
-                break;
-            default:
-                LOG_ALWAYS_FATAL("Unreachable: unsupported wide color space.");
-        }
-        switch (format) {
-            case AHARDWAREBUFFER_FORMAT_R8G8B8A8_UNORM:
-                mWideColorType = SkColorType::kN32_SkColorType;
-                break;
-            case AHARDWAREBUFFER_FORMAT_R16G16B16A16_FLOAT:
-                mWideColorType = SkColorType::kRGBA_F16_SkColorType;
-                break;
-            default:
-                LOG_ALWAYS_FATAL("Unreachable: unsupported pixel format.");
-        }
-    }
-    // This method may have been called when the display config changed, so
-    // sync with the current configuration.
-    ADisplay* primaryDisplay = mDisplays[mPhysicalDisplayIndex];
-    status_t status = ADisplay_getCurrentConfig(primaryDisplay, &mCurrentConfig);
-    LOG_ALWAYS_FATAL_IF(status, "Failed to get display config, error %d", status);
-
-    mWidth = ADisplayConfig_getWidth(mCurrentConfig);
-    mHeight = ADisplayConfig_getHeight(mCurrentConfig);
-    mVsyncPeriod = static_cast<int64_t>(1000000000 / ADisplayConfig_getFps(mCurrentConfig));
-    mCompositorOffset = ADisplayConfig_getCompositorOffsetNanos(mCurrentConfig);
-    mAppOffset = ADisplayConfig_getAppVsyncOffsetNanos(mCurrentConfig);
+void DeviceInfo::onRefreshRateChanged(int64_t vsyncPeriod) {
+    mVsyncPeriod = vsyncPeriod;
 }
 
 std::atomic<float> DeviceInfo::sDensity = 2.0;