Added state to CertificateProvisioning.

[ Cherry-pick of v19 http://go/wvgerrit/219310 ]
[ Merge of http://go/wvgerrit/219453 ]

To enable the CDM to determine between OEM vs DRM responses,
a state variable was needed in CertificateProvisioning.
Previously, the presence/absence of the OEM certificate in the
file system was used; however, if two apps (or single app with
multiple origins) attempts provisioning simultaneously, the
later response would trigger unexpected failures.

The main functional changes this provides is that a more informative
error will be returned to the app if they provide a provisioning
response without ever creating a provisioning request; and that
if multiple clients attempted first-stage provisioning simultaneously,
fewer errors will occur.

Bug: 391469176
Test: run_prov40_tests
Change-Id: I51a118ce73aa809bad6ecee640139a92d8518575

libwvdrmengine/cdm/core/include/certificate_provisioning.h

@@ -72,6 +72,28 @@ class CertificateProvisioning {
   // |default_url| by GetProvisioningRequest().
   static void GetProvisioningServerUrl(std::string* default_url);
 
+  enum State {
+    // Freshly created, not yet initialized.
+    kUninitialized,
+    // A successful call to Init() has been made.
+    kInitialized,
+    // Has generated a DRM request; apps are allowed generate
+    // another one even if a response has not been received.
+    kDrmRequestSent,
+    // Has received (and successfully loaded) a DRM response.
+    kDrmResponseReceived,
+    // Has generated an OEM (Prov 4.0) request; apps are allowed
+    // generate another one even if a response has not been
+    // received.
+    kOemRequestSent,
+    // Has received (and successfully loaded) an OEM response.
+    kOemResponseReceived,
+  };
+  static const char* StateToString(State state);
+
+  // State setter for testing only.
+  void SetStateForTesting(State state) { state_ = state; }
+
  private:
 #if defined(UNIT_TEST)
   friend class CertificateProvisioningTest;
@@ -122,6 +144,9 @@ class CertificateProvisioning {
   CdmResponseType CloseSessionOnError(CdmResponseType status);
   void CloseSession();
 
+  // Tracks the state of CertificateProvisioning.
+  State state_ = kUninitialized;
+
   std::unique_ptr<CryptoSession> crypto_session_;
   CdmCertificateType cert_type_;
   std::unique_ptr<ServiceCertificate> service_certificate_;

libwvdrmengine/cdm/core/include/wv_cdm_types.h

@@ -465,6 +465,7 @@ enum CdmResponseEnum : int32_t {
   GET_DEVICE_INFORMATION_ERROR = 398,
   GET_DEVICE_SIGNED_CSR_PAYLOAD_ERROR = 399,
   GET_TOKEN_FROM_EMBEDDED_CERT_ERROR = 400,
+  PROVISIONING_UNEXPECTED_RESPONSE_ERROR = 402,
   // Don't forget to add new values to
   //  * core/src/wv_cdm_types.cpp
   //  * android/include/mapErrors-inl.h