Add sRGB mode toggle to Viewer.

tools/viewer/sk_app/android/Window_android.cpp

Index: tools/viewer/sk_app/android/Window_android.cpp
diff --git a/tools/viewer/sk_app/android/Window_android.cpp b/tools/viewer/sk_app/android/Window_android.cpp
index 94be02c9336acc1493834c06918dad40ada2bfa7..f2ece45c9816bfb2ab8eb7e53ad58f7ca6b7e387 100644
--- a/tools/viewer/sk_app/android/Window_android.cpp
+++ b/tools/viewer/sk_app/android/Window_android.cpp
@@ -37,12 +37,13 @@ void Window_android::setTitle(const char* title) {
     SkDebugf("Title: %s", title);
 }
 
-bool Window_android::attach(BackEndType attachType, int msaaSampleCount) {
+bool Window_android::attach(BackEndType attachType, int msaaSampleCount, bool srgb) {
     if (kVulkan_BackendType != attachType) {
         return false;
     }
 
     mSampleCount = msaaSampleCount;
+    mSRGB = srgb;
 
     // We delay the creation of fTestContext until Android informs us that
     // the native window is ready to use.
@@ -53,7 +54,7 @@ void Window_android::initDisplay(ANativeWindow* window) {
     SkASSERT(window);
     ContextPlatformData_android platformData;
     platformData.fNativeWindow = window;
-    fWindowContext = VulkanWindowContext::Create((void*)&platformData, mSampleCount);
+    fWindowContext = VulkanWindowContext::Create((void*)&platformData, mSampleCount, mSRGB);
 }
 
 static void android_app_write_cmd(struct android_app* android_app, int8_t cmd) {