Conditionally build support for Pepper-based CDMs.

build/common.gypi

Index: build/common.gypi
diff --git a/build/common.gypi b/build/common.gypi
index e48b6fa338c44f7f6b222728f6795a02712c740c..71276c798fb3d122e8d2d91f70d5729fc3c23e2b 100644
--- a/build/common.gypi
+++ b/build/common.gypi
@@ -1422,6 +1422,12 @@
         'use_cups%': 0,
       }],
 
+      ['enable_plugins==1 and (OS=="linux" or OS=="mac" or OS=="win" or google_tv==1)', {
+        'enable_pepper_cdms%': 1,
+      }, {
+        'enable_pepper_cdms%': 0,
+      }],
+
       # Native Client glibc toolchain is enabled
       # by default except on arm and mips.
       ['target_arch=="arm" or target_arch=="mipsel"', {
@@ -1938,6 +1944,9 @@
       ['enable_viewport==1', {
         'defines': ['ENABLE_VIEWPORT'],
       }],
+      ['enable_pepper_cdms==1', {
+        'defines': ['ENABLE_PEPPER_CDMS'],
+      }],
       ['configuration_policy==1', {
         'defines': ['ENABLE_CONFIGURATION_POLICY'],
       }],