Update build files to use C++17 standard

Updated compiler flags from c++14 to c++17 everywhere.
L3 haystack still uses c++14 and needs more testing.

Bug: 254108623
Test: Build and run CE CDM unit tests
Change-Id: I3883c466705aeb239d22c178605029fec7d46bff

libwvdrmengine/test/java/FullDecryptPathTesting/mobile/build.gradle

@@ -11,7 +11,7 @@ android {
         testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
         externalNativeBuild {
             cmake {
-                cppFlags "-std=c++14"
+                cppFlags "-std=c++17"
             }
         }
     }