Replace WIDEVINE_CDM_AVAILABLE with a gyp define 'enable_widevine_cdm'.

chrome/renderer/media/chrome_key_systems.cc

Index: chrome/renderer/media/chrome_key_systems.cc
diff --git a/chrome/renderer/media/chrome_key_systems.cc b/chrome/renderer/media/chrome_key_systems.cc
index db388eacf9e9486919a00ec3dba99be53e3cd5ac..6fa24e8466fc0e3ef7a816a889a0ce3c066969de 100644
--- a/chrome/renderer/media/chrome_key_systems.cc
+++ b/chrome/renderer/media/chrome_key_systems.cc
@@ -24,7 +24,7 @@
 
 // The following must be after widevine_cdm_version.h.
 
-#if defined(WIDEVINE_CDM_AVAILABLE) && defined(WIDEVINE_CDM_MIN_GLIBC_VERSION)
+#if defined(ENABLE_WIDEVINE_CDM) && defined(WIDEVINE_CDM_MIN_GLIBC_VERSION)
 #include <gnu/libc-version.h>
 #include "base/version.h"
 #endif
@@ -104,7 +104,7 @@ static void AddExternalClearKey(
   concrete_key_systems->push_back(info);
 }
 
-#if defined(WIDEVINE_CDM_AVAILABLE)
+#if defined(ENABLE_WIDEVINE_CDM)
 // This function finds "codecs" and parses the value into the vector |codecs|.
 // Converts the codec strings to UTF-8 since we only expect ASCII strings and
 // this simplifies the rest of the code in this file.
@@ -182,16 +182,16 @@ static void AddPepperBasedWidevine(
                              supported_codecs,
                              concrete_key_systems);
 }
-#endif  // defined(WIDEVINE_CDM_AVAILABLE)
+#endif  // defined(ENABLE_WIDEVINE_CDM)
 #endif  // defined(ENABLE_PEPPER_CDMS)
 
 void AddChromeKeySystems(std::vector<KeySystemInfo>* key_systems_info) {
 #if defined(ENABLE_PEPPER_CDMS)
   AddExternalClearKey(key_systems_info);
 
-#if defined(WIDEVINE_CDM_AVAILABLE)
+#if defined(ENABLE_WIDEVINE_CDM)
   AddPepperBasedWidevine(key_systems_info);
-#endif  // defined(WIDEVINE_CDM_AVAILABLE)
+#endif  // defined(ENABLE_WIDEVINE_CDM)
 #endif  // defined(ENABLE_PEPPER_CDMS)
 
 #if defined(OS_ANDROID)