Segfault When Running Jenkins Tests... Sometimes

(This is a merge of http://go/wvgerrit/71330)

The Service Certificate unit tests actually relied on the ability to
call Properties::Init() multiple times to clear previous mutable state.
Unfortunately, they didn't check the return code that could have told
them their mutable state wasn't being cleared and instead proceeded to
use a pointer which — depending on compiler — could be totally valid and
allow the test to pass or could be invalid and cause a segfault. You can
read the bug for a fuller explanation of the mechanics.

The fix is twofold. First, the tests will now assert out if insertion
into the property set map fails, preventing segfaults. Second, a helper
has been added to Properties that allows tests interested in
re-initializing Properties to do so. The default behavior for most tests
remains the same: Properties can only be initialized once and subsequent
calls to Properties::Init() are ignored.

This patch also fixed a few formatting issues I noticed.

Bug: 123099779
Test: Jenkins Unit Tests w/ GCC
Test: CE CDM Unit Tests w/ GCC & Clang
Change-Id: Ifd29f3ddf5cff934933cf47b92ecd12ab0a4a938

libwvdrmengine/cdm/core/include/properties.h

@@ -85,6 +85,21 @@ class Properties {
                                     CdmClientPropertySet* property_set);
   static bool RemoveSessionPropertySet(const CdmSessionId& session_id);
 
+ protected:
+  // This function always runs the code in |Init()| (and subsequently
+  // |InitOnce()|) even if Properties have already been initialized. This is
+  // needed by certain tests that are dependent on controlling the mutable state
+  // of Properties. Should not be used in general, as most tests rely on
+  // Properties' normal guarantee about |Init()| being safe to call multiple
+  // times without destroying mutable state.
+  static void ForceReinit() {
+    {
+      std::unique_lock<std::mutex> lock(init_mutex_);
+      is_initialized_ = false;
+    }
+    Init();
+  }
+
  private:
   static CdmClientPropertySet* GetCdmClientPropertySet(
       const CdmSessionId& session_id);
@@ -111,7 +126,6 @@ class Properties {
   FRIEND_TEST(CdmLicenseTest, PrepareKeyRequestValidation);
 #endif
 
- private:
   // Called at least once before any properties are used.
   static void InitOnce();