Rename all isolate_dependency_* to files.

net/net_unittests.isolate

Index: net/net_unittests.isolate
diff --git a/net/net_unittests.isolate b/net/net_unittests.isolate
index 53e26745b7bc5cdef71634cfa4ebdde64de96bd5..dafa0d723e5b4cb6f55d2c4f7a2ab9290a17150b 100644
--- a/net/net_unittests.isolate
+++ b/net/net_unittests.isolate
@@ -5,7 +5,7 @@
   'conditions': [
     ['OS=="android" or OS=="linux" or OS=="mac" or OS=="win"', {
       'variables': {
-        'isolate_dependency_untracked': [
+        'files': [
           'data/',
         ],
       },
@@ -18,14 +18,12 @@
           '--brave-new-test-launcher',
           '--test-launcher-bot-mode',
         ],
-        'isolate_dependency_tracked': [
+        'files': [
           '../testing/test_env.py',
-          '<(PRODUCT_DIR)/net_unittests<(EXECUTABLE_SUFFIX)',
-        ],
-        'isolate_dependency_untracked': [
           '../third_party/pyftpdlib/',
           '../third_party/pywebsocket/',
           '../third_party/tlslite/',
+          '<(PRODUCT_DIR)/net_unittests<(EXECUTABLE_SUFFIX)',
           '<(PRODUCT_DIR)/pyproto/',
           'tools/testserver/',
         ],
@@ -34,7 +32,7 @@
     }],
     ['OS=="win" and (fastbuild==0 or fastbuild==1)', {
       'variables': {
-        'isolate_dependency_untracked': [
+        'files': [
           '<(PRODUCT_DIR)/net_unittests.exe.pdb',
         ],
       },