SF/HWC2: Add support for color transforms

Adds support for color transforms using the setColorTransform method
of HWC2.

This means that instead of always falling back to client composition
when applying a transform, SurfaceFlinger will allow the device to
make that decision. If all layers fall back to client composition, the
SKIP_CLIENT_COLOR_TRANSFORM capability allows the device greater
control over whether SF should apply the transform or whether it
should allow the device to apply it to the client target buffer.

Bug: 19539930
Change-Id: I47a3d5453a3c47a8dd105ab77cce7f9c9687e925
diff --git a/services/surfaceflinger/DisplayHardware/HWC2.cpp b/services/surfaceflinger/DisplayHardware/HWC2.cpp
index ae6ba98..87a0e9a 100644
--- a/services/surfaceflinger/DisplayHardware/HWC2.cpp
+++ b/services/surfaceflinger/DisplayHardware/HWC2.cpp
@@ -317,9 +317,12 @@
             "Capability size has changed");
     uint32_t numCapabilities = 0;
     mHwcDevice->getCapabilities(mHwcDevice, &numCapabilities, nullptr);
-    mCapabilities.resize(numCapabilities);
-    auto asInt = reinterpret_cast<int32_t*>(mCapabilities.data());
+    std::vector<Capability> capabilities(numCapabilities);
+    auto asInt = reinterpret_cast<int32_t*>(capabilities.data());
     mHwcDevice->getCapabilities(mHwcDevice, &numCapabilities, asInt);
+    for (auto capability : capabilities) {
+        mCapabilities.emplace(capability);
+    }
 }
 
 bool Device::hasCapability(HWC2::Capability capability) const